DECISION OF THE UPPER TRIBUNAL
(ADMINISTRATIVE APPEALS CHAMBER)

The DECISION of the Upper Tribunal is to allow the appeal by the Appellant.

The decision of the Taunton First-tier Tribunal dated 03 October 2011 under file reference 206/10/00193 involves an error on a point of law and is set aside.

The Upper Tribunal is not in a position to re-make the decision under appeal.  It therefore follows that the Appellant’s appeal against the Secretary of State’s decisions dated 28 September 2009 is remitted to be re-heard by a different First-tier Tribunal, subject to the Directions below.

This decision is given under section 12(2)(a) and 12(2)(b)(i) of the Tribunals, Courts and Enforcement Act 2007.

DIRECTIONS

The following directions apply to the re-hearing:

(1)	     The re-hearing should be at an oral hearing. 

(2)	The new Tribunal should not involve the tribunal judge or other members who sat on the Tribunal that considered this appeal at the hearing in Taunton on 3 October 2011.

(3)	If the Appellant has any further written evidence to put before the tribunal, in particular medical evidence, this should be sent to the regional office of Her Majesty’s Courts and Tribunals Service (HMCTS) in Cardiff within one month of the issue of this decision.  

(4)	The new Tribunal should apply the guidance below in deciding whether or not the Appellant qualifies for the higher rate of the mobility component of disability living allowance (DLA) under either section 73(1)(a) or section 73(3) of the Social Security Contributions and Benefits Act 1992.

(5)	The Secretary of State’s representative should prepare a supplementary submission for the new Tribunal, to be sent to the HMCTS Cardiff office within one month of the issue of this decision, dealing with the matters identified in paragraph 89 below.

(6)	The new Tribunal must consider all the evidence afresh and is not bound in any way by the decision of the previous Tribunal. Depending on the findings of fact it makes, the new Tribunal may end up reaching the same or a different result to the outcome of the previous tribunal.

These Directions may be supplemented by later directions by a Tribunal Judge in the Social Entitlement Chamber of the First-tier Tribunal.  

REASONS FOR DECISION

The question of interpretation at the heart of this Upper Tribunal appeal
1.	What is meant by the statutory expression “a state of arrested development or incomplete physical development of the brain”? This is one, but only one, of a number of tightly defined conditions which must be satisfied under the “severe mental impairment” (SMI) rules in order to qualify for the higher rate of the mobility component of disability living allowance (DLA). It is the main issue arising on this appeal.

The Upper Tribunal’s conclusion on a point of law
2.	Social Security Commissioner’s decision R(DLA) 2/96 has long been recognised as authority for the proposition that the human brain is fully developed before an adult reaches the age of 30. On that basis it has been consistently held that a person who suffers from what would otherwise be regarded as “a state of arrested development or incomplete physical development of the brain” does not qualify under the SMI rules if that condition first occurs after the age of 30 (e.g. as a result of traumatic brain injury). I refer to this as the “age 30 cut-off rule”. In the light of the expert evidence reviewed in this decision, I decide that the age 30 cut-off rule is no longer good law and R(DLA) 2/96 should no longer be followed in that respect.

The implications in a nutshell for this particular case
3.	In summary I conclude that the First-tier Tribunal went wrong in law because it applied the age 30 cut-off rule. The Tribunal’s decision is accordingly set aside. The Appellant’s appeal will have to be re-heard by a new Tribunal which must consider afresh whether or not he meets the requirements of all the SMI rules. These raise at least three questions. First, does the Appellant suffer from “a state of arrested development or incomplete physical development of the brain”? The answer may well be yes, for the reasons that follow, but that is ultimately a question for the new Tribunal. Secondly, however, the Tribunal will need to be satisfied that this condition “results in severe impairment of intelligence and social functioning”. That may not be straightforward. Thirdly, and potentially more problematically, the Appellant will also need to show that he suffers from “severe behavioural problems”, at least in the narrow sense in which that expression is defined by the regulations. Each of these three questions will require careful fact-finding by the new Tribunal.

The factual circumstances of this appeal
4.	The Appellant, a man aged 48, was involved in a near fatal road traffic accident (RTA) in Ireland in 1998, when he was aged 32. The circumstances of the RTA are unclear. It is not known if a third party was involved. It is likely that the accident occurred sometime before, and possibly days before, the Appellant was actually found by the emergency services. He was on life support for 3 weeks, fed through a tube for 5 months and in hospital for more than 6 months. The Appellant now suffers from severe mood swings and lives in a chronic confusional state – for example, he still thinks he lives in Stockport, where he lived decades ago, despite having lived in Somerset for nearly two decades.

5.	The Appellant is now cared for by his mother; however, she had been supported in that role by the Appellant’s step-father, until sadly he passed away in January 2009. According to his GP, writing back in 2003 (all emphasis as in the original), “*THIS MAN NEEDS CONTINUOUS SUPERVISION.* If it were not for the heroic efforts of his mother and step-father, he would be in institutional care. Every aspect of his life requires supervision and this is relentless.” The same GP, writing in November 2009, described the Appellant’s injuries in the following terms:

“He sustained very severe head injuries and was not expected to survive. He fractured his left temporal bone and suffered multiple intracerebral haemorrhages with significant brain damage. He also suffered severe left sided facial injuries with a fracture to the floor of his left orbit.”

6.	The GP then continued with this detailed description of the Appellant’s circumstances (there is no suggestion they are appreciably different today):

“He has been left with severe permanent brain damage causing a chronic confusional state. He has severe cognitive impairment with disorientation in place, time and situation. He has no short term memory and his long term memory has also been affected. He needs continuous prompting and supervision for all tasks of daily living. In functional tasks he has difficulty with initiation, persistence and sequencing. He has no appreciation of danger. He will never drive and will never be able to use public transport unaccompanied. Though his physical injuries have improved his severe irreparable brain damage has led to permanent disability with no prospect of improvement. Another consequence of the brain injury is emotional lability with occasional aggressive outbursts. Unfortunately his stepfather died unexpectedly in January 2009. There have been significant behavioural problems since then and a deterioration in his function. His short term memory is so poor that he has to be reminded regularly of his step-father’s death thus causing a daily reliving of the bereavement.”

The Appellant’s disability living allowance claims and the adjudication history
7.	A decision maker awarded the Appellant the highest rate of the care component of DLA and the lower rate of the mobility component for the period from 5 September 2000 to 4 September 2003 (revised decision dated 24 April 2003). On renewal, the award was changed to the middle rate care component and lower rate mobility component for the period from 5 September 2003 to 4 September 2006 (decision dated 12 June 2003). On 25 March 2004 an appeal tribunal allowed an appeal against that reduced renewal award, reinstating the award of the highest rate care component and confirming the lower rate mobility component for an indefinite period.

8.	On 14 September 2009 the Appellant’s mother (and appointee) applied for the mobility component to be increased to the higher level, citing his increased mobility needs and providing detailed supporting evidence. This was technically an application for a supersession of the previous appeal tribunal’s award from 2004. On 24 September 2009 a decision maker referred the papers to a health care professional (HCP) for desk-based advice, asking whether there was “arrested or incomplete development of the brain” and, if so, whether there was severe impairment of intelligence and social functioning together with severe behavioural problems. The HCP’s advice the following day was short and to the point:

“As this 43 year old man suffered RTA [road traffic accident] after the age of 30 years of age he does not qualify under rules of SMI. As this is the case there is no reason to answer IQ or behavioural questions.”

9.	In other words, the view was that because the Appellant had suffered his injuries after the age of 30, he therefore could not be said to suffer from a state of “arrested or incomplete development of the brain”. As will be seen, that understanding reflected the position in the case law. In the light of that advice, on 28 September 2009 the decision maker refused to supersede the earlier decision, and so confirmed the existing appeal tribunal award of the highest rate care component with the lower rate mobility component for an indefinite period. The Appellant’s mother then lodged an appeal on his behalf. In doing so she received considerable assistance from a family friend, Dr Harris, who provided detailed written submissions on both the medical and legal aspects of this difficult case. 

10.	A First-tier Tribunal considered the appeal on 14 May 2010 but adjourned for an examining medical practitioner (EMP)’s report, which was completed on 8 September 2010. The matter then came back before another First-tier Tribunal on 4 July 2011, which adjourned for submissions on human rights points that had been raised. The case finally came back before a First-tier Tribunal (“the Tribunal”) on 3 October 2011.

11.	The Tribunal’s decision at this final hearing was to dismiss the appeal, but again confirming the Appellant’s ongoing entitlement to indefinite awards of the highest rate care component and the lower rate mobility component. So the 2011 Tribunal came to the same conclusion as the 2004 appeal tribunal.

The SMI route to entitlement to the higher rate mobility component
12.	At this juncture it is important to revisit the special criteria for entitlement to the higher rate mobility component of DLA through the SMI route. There are three core conditions, each of which must be satisfied and each of which has a number of separate elements (Social Security Contributions and Benefits Act [“SSCBA”] 1992, section 73(1)(c) and (3)). The first core condition is that the claimant is “severely mentally impaired” (SSCBA 1992, section 73(3)(a)). The second is that he “displays severe behavioural problems” (SSCBA 1992, section 73(3)(b)). The third is that he qualifies for the highest rate of the care component of DLA (SSCBA 1992, section 73(3)(c)). These are different to, and more challenging by comparison with, other statutory definitions of the expression “severe mental impairment” (contrast e.g. paragraph 2 of Schedule 1 to the Local Government Finance Act 1992 for the purposes of council tax).

13.	In the present case the proceedings before both the First-tier Tribunal and the Upper Tribunal have been exclusively focussed on whether the Appellant meets the first of those three conditions. There have been no findings of fact as to whether the second condition has been met. However, given the terms of the existing DLA award, it is agreed that the third condition is satisfied in this case.

14.	Applying the ordinary English meaning of the words of the primary legislation, and without any further gloss on their meaning, I am confident that any lay person or doctor would agree that the Appellant is “severely mentally impaired”. That was certainly the view of the Appellant’s GP (as she wrote, “I understand that the opinion is still that he does not qualify as having a ‘severe mental impairment’. I cannot understand this as he has extremely poor short term memory and needs supervision at all times ... I have never had a patient with such severe mental impairment fail to obtain the highest level of disability living allowance” (letter dated 1 July 2011)).

15.	However, the test for the first condition under section 73(3) is not simply a matter of applying the meaning of those ordinary English words in the statute. The relevant secondary legislation (regulation 12(5) of the Social Security (Disability Living Allowance) Regulations 1991 (SI 1991/2890; “the 1991 Regulations”)), as amended) defines ‘severe mental impairment’ as follows:

“(5) A person falls within subsection (3)(a) of section 73 of the Act (severely mentally impaired) if he suffers from a state of arrested development or incomplete physical development of the brain, which results in severe impairment of intelligence and social functioning.”

16.	So the “plain English” reading of “severely mentally impaired” is not enough. The claimant must meet the specific test set out in regulation 12(5). Similarly, a plain English reading of the second condition in the primary legislation, “severe behavioural problems”, will not suffice – instead, the especially demanding three-fold test laid down in regulation 12(6) must be satisfied. I return to that later (see paragraphs 83-87 below).

The Tribunal’s decision and reasoning
17.	The Tribunal which sat on 3 October 2011 correctly identified that the question of entitlement to the highest rate care component was not in dispute. Equally, it noted that the conditions for an award of the lower rate mobility component were obviously met. It therefore isolated the issue it had to decide as being whether or not the Appellant “was entitled to receive the higher rate mobility component through the SMI route” (statement of reasons, paragraph 17). The Tribunal reluctantly dismissed the appeal, expressing its very considerable sympathy for the Appellant and his family and its admiration for the way in which the case had been put. The Tribunal’s reasoning was encapsulated in paragraph 18 of the statement of reasons (retaining the original syntax):

“18. Of particular importance in this case is Regulation 12(5) and Regulation 12(6) of the 1991 Regulations. The issue therefore now for the Tribunal was whether [the Appellant] suffered from a state of arrested development or incomplete physical development of the brain which resulted in severe impairment of intelligence and social functioning. The Tribunal considered a number of Social Security Commissioners’ Decisions being CDLA/156/94, CDLA/393/94, R(DLA) 3/98, CDLA/1678/97, M (A Child v Adjudication Officer) [reported as R(DLA) 1/00] and also CDLA/5153/97. We considered all of these decisions in our discussion as a Tribunal when considering our decision. However, we have concluded, looking at the decisions of the Commissioners by which we are bound to follow and in particular CDLA/1678/97 in conjunction with CDLA/156/94. The evidence in this case was that the Appellant suffered a tragic road traffic accident when a young man in 1998 when he was approximately 32 years of age. Within the terms of the two Commissioners’ decisions latterly mentioned, we thought that the circumstances of [the Appellant] were that there was not incomplete development of the brain nor arrested development of the brain and therefore sub-paragraph (5) of Regulation 12 were not met in this case”.

18.	At this stage I just make two observations about that passage. The first is that although the Tribunal identified regulations 12(5) and 12(6) as being of importance, it only stated a conclusion as regards the first SMI condition, as defined by regulation 12(5). The second is that the Tribunal’s mention of Commissioner’s decision CDLA/156/94 was a reference to a decision of Mr Commissioner Rice’s, which was subsequently reported as R(DLA) 2/96. Plainly the Tribunal regarded itself as bound by R(DLA) 2/96 and CDLA/1678/1997 to conclude, on the facts of this case, that the regulation 12(5) test was not satisfied. In short, it applied the age 30 cut-off rule.

The proceedings before the Upper Tribunal
19.	Permission to appeal was initially refused by the District Tribunal Judge. The application was then renewed before the Upper Tribunal by Dr Harris on the Appellant’s behalf. Judge Lane gave limited permission to appeal on two grounds. The first ground was Dr Harris’s human rights challenge, namely his argument that the “severe mental impairment” test amounted to unlawful indirect discrimination on the ground of age. The second ground, identified by Judge Lane in the exercise of her inquisitorial function, was whether, in applying regulation 12(5), the Tribunal had erred in law by failing to consider and/or apply the decision of Upper Tribunal Judge Levenson in SC v Secretary of State for Work and Pensions [2010] UKUT 76 (AAC). 

20.	Those two grounds have since been supplemented by a third point. In the initial written submissions on the appeal, Dr Harris for the Appellant had queried whether R(DLA) 2/96 remained good law. I regarded this point as a natural extension of the second ground of appeal on which Judge Lane had given permission and directed further submissions on the issue. In particular, I directed the Secretary of State’s representative to provide an expert report dealing with the current medical understanding of the development of the brain, given that R(DLA) 2/96 had cited such expert evidence but the case was now nearly two decades old. Those directions posed the following questions:

“What is now understood by medical scientists by the expression ‘a state of arrested development or incomplete physical development of the brain’? Further, to what extent does the brain develop throughout life?”

21.	The Secretary of State duly commissioned an extremely helpful report entitled Human brain development: When does the human brain stop developing?, prepared by Professor Sarah-Jayne Blakemore, Royal Society Research Fellow and Professor of Cognitive Neuroscience at University College London. I subsequently held an oral hearing of the appeal at Field House in London on 4 June 2014. The Appellant was ably represented by Mr Charles Newington-Bridges of Counsel, acting pro bono, while the Secretary of State was efficiently represented by Mr Jeremy Heath, Solicitor, of the Office of the Solicitor to the DWP. I am indebted to them both for their detailed oral and written arguments. I did not hear oral evidence from Professor Blakemore herself, as the expert report was not in dispute. 

22.	I shall deal with the three grounds of appeal in reverse order. First, is Mr Commissioner Rice’s decision in R(DLA) 2/96 still good law as to the proper understanding of “severe mental impairment”, and in particular as to the meaning of “incomplete physical development of the brain”? Second, did the Tribunal err in law by disregarding Judge Levenson’s more recent decision in SC v Secretary of State for Work and Pensions? Third, are section 73(3) of the SSCBA 1992 and regulation 12(5) of the 1991 Regulations in breach of human rights law? The starting point therefore has to be the existing Social Security Commissioners’ precedents relied upon by the Tribunal in this case.

Ground 1: is R(DLA) 2/96 still good law on “severe mental impairment”?
The existing Commissioners’ precedents: R(DLA) 2/96 and CDLA/1678/1997
23.	The first precedent relied upon by the Tribunal was R(DLA) 2/96 where the claimant, whose age was not stated in the case report but who was evidently over 30, suffered from Alzheimer’s disease. The appeal tribunal had found that she was not entitled to the higher rate of the mobility component of DLA as she did not meet the first SMI condition, as further defined by regulation 12(5) of the 1991 Regulations. Mr Commissioner Rice set aside the appeal tribunal’s decision for inadequate reasons, but substituted his own decision to the same effect, having heard expert medical and scientific evidence. The head-note to the reported decision accurately summarises the Commissioner’s decision in the following terms: “the current state of the medical authorities indicated that the brain was fully developed before a person reached the age of 30. Alzheimer’s disease caused a gradual but inevitable loss of brain cells, eroding an already developed brain. Thus a sufferer from it did not fall within regulation 12(5).”

24.	In R(DLA) 2/96 Mr Commissioner Rice heard expert evidence from a Dr M.N. Rosser MA, MB, B Chir, MRCP, MD and FRCP, a consultant neurologist and expert on Alzheimer’s disease, called on behalf of the claimant, and from Professor D.C. Taylor, MB, BS, MD, MSc, FRCP, FRC Psych. and DPM (London), a consultant in neuropsychiatry, called on behalf of the Secretary of State. In an important passage in his reasoning, having posed the question “does the brain develop throughout life?”, Mr Commissioner Rice concluded as follows (with original emphasis):

“13. On the medical evidence, I am not satisfied that it does. I prefer the approach of Professor Taylor, that the brain, like all physical attributes of a human being, reaches a point of ultimate development, and goes no further. Dr. Rossor admitted that modern researches were at the very frontiers of knowledge in this field, and was not prepared to say with unequivocal conviction that the brain could develop throughout life by reason of the acquisition of new skills. Although he was inclined to take the view that, on balance, such was the case, he did so with no complete confidence, and on the balance of probability I am satisfied that it has not yet been established that the brain develops after it has achieved its maximum size and weight. I consider that, in so far as the brain changes to reflect the acquisition of new skills, this is but the exercise of the brain, not its further development. The brain is equivalent to the “hardware”, and although its function may be improved by the introduction of “software”, the hardware is constant and cannot be improved. Moreover the processes and connections would seem to me to be in the nature of repairs to and maintenance of the brain rather than it development. It follows that, if the brain cannot be developed after it has achieved its maximum size and weight, there can be no question of a sufferer from Alzheimer’s disease being subject to "incomplete physical development of the brain". I am reinforced in this conclusion by the fact that any other view would result in there being no restriction imposed by regulation 12(5). Everyone by definition would during his life have a brain which could never be said to have been completely developed, and the restriction of regulation 12(5) would be meaningless, something which should only be accepted if no other interpretation were possible.”

25.	As Mr Heath noted, for the past two decades R(DLA) 2/96 has been recognised as the leading case law authority on the meaning of the first half of regulation 12(5), namely whether a person “suffers from a state of arrested development or incomplete physical development of the brain”. As such, it was the basis for the HCP’s original and rather dismissive response to the inquiry from the decision maker in the Appellant’s case. Mr Heath helpfully sought to derive three main propositions of law from the reasoning in Mr Commissioner Rice’s decision.

26.	Proposition 1 was that where an adult acquires new skills (e.g. learning a foreign language or learning to play a musical instrument), this involves the exercise of the functions of the brain, rather than the further development of the brain (R(DLA) 2/96 at paragraphs 8-10).

27.	Proposition 2, which was the main point highlighted by the head-note to the decision, was that the brain attained full development in each individual before the age of 30 (R(DLA) 2/96 at paragraph 10). At one point the Commissioner concluded, preferring the evidence of Professor Taylor to Dr Rosser, that the human brain reached its full development “in most cases in the late twenties” (paragraph 10, line 11). Later in the same paragraph, however, the same finding was put in absolute and categorical terms: “the brain attained full development in the case of each individual by a specified time which was invariably before the age of 30. There could be no question of any further development” (R(DLA) 2/96, paragraph 10, lines 19-20, emphasis added).

28.	Proposition 3 was that if a child’s brain had failed to grow in the proper way, and this could be physically seen, this constituted “incomplete physical development” within regulation 12(5). However, where there was apparently nothing physically wrong with the brain, but its functioning was nevertheless deficient in some way, then that amounted to “arrested development” (see R(DLA) 2/96, paragraph 11). I return to this point in the context of the second ground of appeal.

29.	The second authority relied upon by the Tribunal in the present appeal was CDLA/1678/1997, another decision of Mr Commissioner Rice, which concerned a child with autism. In that case the Commissioner accepted that the claimant suffered from “a state of arrested development or incomplete physical development of the brain” within regulation 12(5) (at paragraph 7), but concluded on the facts that the child did not suffer severe impairment of intelligence (at paragraph 12). It follows that CDLA/1678/1997 was not actually relevant to the instant case, and need not be considered further.

Professor Blakemore’s expert report and propositions 1 and 2
30.	Professor Blakemore is on any reckoning pre-eminent in her field of scientific research. She has published over 95 papers in peer-reviewed scientific journals, which have been cited over 10,000 times. She is Leader of the Developmental Cognitive Neuroscience Group at the UCL Institute of Cognitive Neuroscience and Editor-in-Chief of the learned journal Developmental Cognitive Neuroscience. It is unnecessary to refer to her formal qualifications and prizes of distinction; both Mr Heath and Mr Newington-Bridges were more than content to accept her report as authoritative and expert on the current state of knowledge as to the development of the brain. There are inevitably dangers in seeking to distil the main messages from Professor Blakemore’s detailed 16-page report for the purposes of this decision, but Mr Newington-Bridges has helpfully summarised her key findings as follows (skeleton argument, paragraph 42). I did not understand Mr Heath to suggest that this was otherwise than a fair summary of this complex area of knowledge:

“(a) Advances in brain imaging technology, in particular magnetic resonance imaging, have allowed neuroscientists to examine the human brain at all ages to track developmental changes in the brain’s structure [para 3];

(b) This has revealed that development does not stop in childhood as had previously been thought, but continues throughout adolescence and well into adulthood [para 3];

(c) Several brain regions continue developing into adulthood most of which are situated in the cortex. The prefrontal cortex, temporal cortex and parietal cortex all undergo protracted development [para 4];

(d) White matter volume throughout the brain increases during the first four decades of life [para 4]; 

(e) A further finding of MRI studies is that grey matter – which contains a mix of cell bodies, blood vessels and connections between cells/synapses (i.e. physical matter) declines during childhood and adolescence and in fact that declines continue into adulthood and only level off between the late twenties and up to 50 years [para 6]. This finding is explained later in the report in which Professor Blakemore states that changes in the number of synapses throughout development probably, at least, in some part, underlie the pattern of change in grey matter volume [para 9];

(f) Experience-expectant plasticity may be defined as the readiness of the brain to respond to sensory input from the environment during development e.g. the readiness of a young child to be exposed to sounds and thereby to learn a language [para 10];

(g) Sensitive periods of development in this respect may be due to synaptic reorganization: which synapses are strengthened and which are pruned depends on environmental input [para 10];

(h) It is possible that this experience-expectant process might continue into adolescence for certain functions and certain brain areas. However, this is not to say that the brain is incapable of change in adulthood. The question of when the brain stops developing is misleading because the brain does not cease being capable of change [para 11];

(i) The plasticity that occurs into adulthood is known as experience-dependant plasticity e.g. learning to play a musical instrument or to play tennis later in life would involve experience-dependant plasticity. There is no age limit to this type of learning [para 11].”

31.	It is perhaps best if I quote Professor Blakemore’s conclusion in her own words:

“15. Neuroscience research carried out in the past 15 years indicates that the human brain undergoes protracted development until at least the third decade of life. Different brain regions develop at different rates and cease developing at different ages. The precise age at which an individual’s brains stops developing probably depends on multiple factors, including genetic and environmental influences, and the question as to when the brain stops developing is in some way unanswerable. However, my understanding of the extent literature leads me to conclude that the brain will have ceased developing, in terms of experience-expectant changes in grey matter and white matter, by the thirties or early forties in most people. It might be useful to consider the age at which brain development ceases as a broad age range rather than a specific number of years. Moreover, we do not know how this relatively protected brain development corresponds to functional development in terms of cognition and behaviour. Even though brain development seems to level off at some point, neuroplasticity, the way the brain adapts to changing environmental stimuli, is a baseline state that happens whenever learning takes place and has no age limit.”

The implications of Professor Blakemore’s expert report for R(DLA) 2/96
Introduction
32.	It is clear that on any reading Professor Blakemore’s expert report requires a reappraisal of the findings in R(DLA) 2/96. This should not come as any surprise. In R(DLA) 2/96 itself Mr Commissioner Rice had recorded the view of one of the experts that “this whole area of medicine was at the very frontiers of knowledge” (at paragraph 8). But as Professor Blakemore now observes:

“3. Until about 15 years ago it was assumed that the vast majority of brain development takes place during the first few years of life. Up until that point, scientists did not have the technology to look inside the living, developing human brain. In the past decade, however, mainly due to advances in brain imaging technologies, in particular magnetic resonance imaging (MRI), neuroscientists have started to examine the living human brain at all ages in order to track developmental changes in the brain’s structure...”

33.	So where does this leave the first two of the three propositions of law derived by Mr Heath from R(DLA) 2/96 (leaving the third to be considered further below in the context of the second ground of appeal)?

Proposition 1: new skills involve the exercise not the development of the brain
34.	Proposition 1 from R(DLA) 2/96 was that where an adult acquires new skills this involves the exercise of the functions of the brain, rather than the further development of the brain. In doing so Mr Commissioner Rice had preferred the view of Professor Taylor, namely that at most the brain may have changed (some skills might be acquired whilst others discarded) but did not as such develop, over that of Dr Rosser (at paragraphs 8-10). Mr Newington-Bridges and Mr Heath were agreed that Mr Commissioner Rice’s analysis could no longer stand in the light of Professor Blakemore’s evidence. According to her expert report, the human brain retains a degree of experience-dependent plasticity throughout adulthood:

“learning to play tennis, a musical instrument, or new computer software are examples of tasks that require experience-dependent plasticity. There is no age limit to this kind of learning ...” (paragraph 11).

35.	Professor Blakemore gives the following instructive example in her report, arising out of the unique skill-set of London taxi-drivers, known as “The Knowledge”, to demonstrate that this may involve physical development of the brain well into adulthood (footnote 22 referred to the research paper by E. Maguire et al., “Navigation-related structural change in the hippocampi of taxi drivers”, Proc. Natl. Acad. Sci. U.S.A. (2000) 97: 4398-4403):

“12. It is important to point out that experience-dependent plasticity is a baseline state – it is occurring all the time in the brain, whenever a new memory is laid down or a new face is seen. An example of experience-dependent plasticity is found in the hippocampus, which is a structure deep inside the brain that is essential for spatial navigation and spatial memory. Researchers have compared the hippocampus in London taxi-drivers, whose spatial memory of the lay-out of London has to be extremely advanced, with that of non-taxi drivers. The posterior hippocampus was significantly larger in taxi drivers and its size was related to the number of years the person had been driving taxis, suggesting that its size depends on the degree to which an individual uses their spatial memory.22 In summary, experience-dependent plasticity occurs throughout life and occurs wherever you learn something new.”

36.	In the light of Professor Blakemore’s expert evidence I am satisfied that whereas Proposition 1 in R(DLA) 2/96 may have reflected the consensus of scientific understanding at the time that case was decided (July 1995), the position is very different now. Where an adult learns new skills, this may involve the physical development and not merely the exercise of the brain. However, as Mr Heath rightly observed, the validity or otherwise of Proposition 1 in R(DLA) 2/96 is not a “make or break point” for the decision in the case currently under appeal. That depends very much on Proposition 2.

Proposition 2: the brain attains full development before the age of 30
37.	Proposition 2 from R(DLA) 2/96 was that the brain attained full development in each individual before the age of 30. Depending on which passage in paragraph 10 of R(DLA) 2/96 was given greater emphasis, this was stated in qualified or absolute terms. Mr Newington-Bridges and Mr Heath correspondingly differed in their submissions. Mr Newington-Bridges pointed to Professor Blakemore’s evidence that the physical volume of the brain is changing at least into the fourth decade of life, and perhaps into the 50s, with an increase in white matter and a decrease in grey matter. As a result, Proposition 2 could no longer stand in the light of contemporary scientific knowledge. It followed that the simple fact that the Appellant had suffered his injuries at the age of 32 did not prevent him from suffering from a state of arrested development or incomplete physical development of the brain within the meaning of regulation 12(5). Mr Heath argued for a more nuanced interpretation than in R(DLA) 2/96. He argued that Mr Commissioner Rice’s finding that the brain had reached full development “in most cases in the late twenties” was an oversimplification, and that a larger age range applied. However, he accepted that Mr Commissioner Rice’s conclusion that the brain “invariably” attained full development before the age of 30 could not stand in the light of Professor Blakemore’s evidence.

38.	The difference between the two representatives’ arguments is perhaps one of emphasis. On balance, however, I prefer Mr Newington-Bridges’s submissions on this point. Professor Blakemore’s expert evidence demonstrates that the basis for the decision in R(DLA) 2/96 simply cannot stand in the light of modern medical and scientific understanding. As this case itself demonstrates only too well, the reality is that for the past two decades R(DLA) 2/96 has been treated as authority for the proposition that the brain reaches its full development by the age of 30. That “headline” proposition, which underlies the age 30 cut-off rule, is simply wrong in the light of Professor Blakemore’s report. Her evidence also gives no real support for the more qualified proposition that the adult brain has reached full development “in most cases in the late twenties”. For example, as regards white matter – which contains axons, the long fibres attached to neurons (brain cells) along which electrical signals pass – “white matter volume appears to stop increasing at some point in the thirties or early forties” (paragraph 5). On the other hand, the volume of grey matter – which contains a mix of cell bodies, blood vessels and synapses (connections between cells) – is at its peak during childhood and decreases during adolescence, a decline that “levels off at some point in adulthood between the late twenties and up to 50 years” (paragraph 6). In addition, I must not lose sight of Professor Blakemore’s evidence about the brain’s experience-dependant plasticity in the context of Proposition 1 above – namely that “the question of when the human brain stops developing is misleading because the brain does not cease being capable of change at any age” (paragraph 11).

39.	I am in no doubt that the conclusions above would have come as a great surprise to those responsible for drafting regulation 12(5) of the 1991 Regulations. At that time, as Professor Blakemore acknowledged, it was simply assumed that the vast majority of brain development takes place during the first few years of life. As I wrote in the textbook The Law of Social Security (Wikeley, Ogus and Barendt, 5th edition, 2002, p.689, omitting footnote):

“The original intention behind this formulation [regulation 12(5)] was to limit entitlement to claimants who were severely mentally impaired from birth or from early childhood, on the basis that the human brain is not fully developed until the age of about five years old. It was therefore envisaged that it would cover a child aged four who was severely disabled as a result of falling out of a tree or an attack of meningitis, but not a teenager injured as a result of a motorcycle accident”.

40.	Mr Commissioner Rice’s decision in R(DLA) 2/96 accordingly represented a considerable increase in the potential age range for those seeking to establish entitlement to the higher rate mobility component under the SMI rules. The age 30 cut-off rule was based on the best scientific evidence available at the time. Two decades on, the phrase “a state of arrested development or incomplete physical development of the brain” has to be construed in the light of today’s expert evidence. Modern scientific knowledge demonstrates that there is no age 30 cut-off rule. According to Professor Blakemore, “the question as to when the brain stops developing is in some way unanswerable”. The best we can say, on the basis of her expert evidence, is that “the brain will have ceased developing, in terms of experience-expectant changes in grey matter and white matter, by the thirties or early forties in most people” but that “neuroplasticity, the way the brain adapts to changing environmental stimuli, is a baseline state that happens whenever learning takes place and has no age limit.” 

41.	This obviously poses a real and possibly insuperable challenge for tribunals when seeking to apply the terms of regulation 12(5) to the circumstances of a particular case. It may not be unreasonable to say that experience-dependent plasticity occurs at the margins, and so a tribunal may reasonably focus on physical development of the brain in terms of white and grey matter. Obviously it will be wholly unrealistic to identify the specific age at which such changes cease in a particular individual, as the evidence will simply not be available. However, a tribunal is entitled to apply the balance of probabilities. On that basis, given that the Appellant in the present case was aged 32 at the time of his accident, and that falls very much towards the bottom end of the age range identified by Professor Blakemore’s evidence, then for myself I agree with Mr Newington-Bridges that it would be reasonable to say that the Appellant’s brain had not completely developed. Ultimately, however, this is a question of fact for the new Tribunal. For present purposes it is sufficient to record my view that R(DLA) 2/96 should not be followed in so far as it holds or implies that regulation 12(5) embodies the age 30 cut-off rule. 

42.	Thus the Tribunal, in concluding that the Appellant was absolutely barred by virtue of his age from meeting the regulation 12(5) test, erred in law. The first ground of appeal is therefore made out.

Ground 2: should SC v Secretary of State for Work and Pensions have applied?
The two possible readings of regulation 12(5)
43.	The second ground of appeal relates to a separate point on the proper construction of regulation 12(5). The issue may be put in the following terms. A claimant only qualifies under the regulation “if he suffers from a state of arrested development or incomplete physical development of the brain”. The question that then arises is whether the words “of the brain” qualify both “arrested development” and “incomplete physical development” (“Meaning 1”), or whether they relate only to “incomplete physical development” (“Meaning 2”). As a matter of syntax, either reading is plausible. So Meaning 1 might be re-phrased as follows: “does the Appellant suffer from arrested development of the brain or incomplete physical development of the brain”? On the other hand Meaning 2 might be expressed in this way: “does the Appellant suffer from either (1) a state of arrested development; or (2) incomplete physical development of the brain?” 

The approach taken in R(DLA) 2/96
44.	In R(DLA) 2/96 Mr Commissioner Rice clearly adopted Meaning 1. Indeed, it does not appear to have been argued before him that “arrested development” meant anything other than “arrested development of the brain”. The Commissioner concluded as follows (at paragraph 11), noting the agreed position of the medical experts in that case:

“... where a child’s brain failed to grow in the proper way, and this could be physically seen, then there was ‘incomplete physical development’. Where, however on examination of a child’s brain there was nothing which appeared to be physically wrong with it, but the function of the brain was nevertheless deficient, then it was said that there was an ‘arrested development’. What was missing was not apparent physically, but the consequences of the deficiency were only too apparent.”

The approach taken in SC v Secretary of State for Work and Pensions
45.	However, when giving permission to appeal in this case, Judge Lane drew attention to the more recent decision of Judge Levenson in SC v Secretary of State for Work and Pensions, which concerned a 9 year old girl with Down’s Syndrome. The claimant had been awarded the highest rate care component and the lower rate mobility component on a DLA renewal claim and appealed, seeking the higher rate mobility component. A First-tier Tribunal, by a majority, confirmed the Department’s renewal award and dismissed the girl’s appeal (the dissenting member, however, took the view that the claimant was virtually unable to walk). Judge Levenson allowed the Appellant’s further appeal, set aside the tribunal’s decision and remitted the case for re-hearing before a new tribunal. In doing so he observed as follows on the terms of regulation 12(5):
 
“Severely Mentally Impaired

28. The meaning of severely mentally impaired is found in regulation 12(5), which is set out above. The First-tier Tribunal found that there was no evidence of ‘arrested or incomplete development of the brain’. However, this is a common but mistaken paraphrase of regulation 12(5), which refers to ‘arrested development’ or ‘incomplete physical development of the brain’. There are two aspects to this error. One is that a distinction is drawn between arrested development generally (not limited to the brain, although there must still be a physical cause) and incomplete physical development of the brain. The other is that ‘arrested development’ does not mean arrested physical development (otherwise the regulation would say so, as it says ‘incomplete physical development’). Thus, regulation 12(5) can apply to a person who has arrested emotional or functional development which has a physical cause even if that cause is not related to the development of the brain.”

46.	In her grant of permission, Judge Lane referred to SC in the following somewhat sceptical terms:

“It is also arguable that the Tribunal erred in law in failing to consider and/or apply SC v SSWP [2010] UKUT 76 (AAC) [CDLA/1621/2009] in which Upper Tribunal Judge Levenson interpreted regulation 12(5) in a novel way to apply to a person who had arrested emotional of functional development through a physical cause, even if that cause is not related to the development of the brain. If this decision is correct, it substantially widens the applicability of the severe mental impairment (SMI) provisions for the higher rate of the mobility component. It is by no means clear that Judge Levenson’s interpretation is sustainable, and I am not necessarily to be taken to agree with the decision.”

47.	At this juncture it is necessary to refer back to Professor Blakemore’s helpful expert report.

Professor Blakemore’s expert report and proposition 3
48.	Professor Blakemore’s expert report advises that the phrase “arrested development” is “arguably unhelpful and misleading” and so is not commonly used either clinically or in neuroscience these days, as it implies that no recovery of function can take place. She points out that today a range of alternative medical terms are used, such as “developmental regression”, “functional/cognitive impairment” and “developmental delay”, which she defines as follows. 
	
49.	“Developmental regression” describes the progressive loss of skills after having reached particular developmental milestones. It is not typically used after traumatic brain injury as it refers to a gradual process of deterioration, such as may be caused by some genetic disorders and neurodegenerative conditions.

50.	“Functional/cognitive impairment” is where a person no longer demonstrates the same skills as before, or the skills that would be expected for their stage in development, and is often the consequence of brain injury. Such impairment may sometimes be improved through training and rehabilitation.

51.	“Developmental delay” refers to the ongoing process of acquiring skills and is often used to describe the situation where a child is not developing as expected in one or more areas (or, if in all areas, “global developmental delay”). Such developmental delay may have multiple causes, e.g. genetic conditions, pre-natal exposure to harmful substances, childhood illness or neglect and indeed brain injury. As with functional/cognitive impairment, training and rehabilitation may result in significant improvement.

The parties’ submissions
52.	Mr Newington-Bridges, for the Appellant, argued that Judge Levenson was correct in SC to conclude that regulation 12(5) referred to two discrete component parts in accord with Meaning 2, namely (1) “a state of arrested development” and alternatively (2) “incomplete physical development of the brain”. He supported this submission by reference to various principles of statutory construction (e.g. the presumption against surplusage). Thus, Mr Newington-Bridges contended, “arrested development refers to development that has ceased, which is not limited to the brain otherwise the words ‘of the brain’ would have been used. It does not just mean physical development otherwise the word physical would have been used” (skeleton argument at paragraph 58). In the present case, the Appellant’s cognitive and/or emotional and/or functional development had been arrested by the accident, so he fell within the terms of regulation 12(5).

53.	Mr Heath explained that the Secretary of State’s position was that “arrested development” referred to arrested development of the brain, rather than arrested development in some wider sense. Accordingly, the Department did not accept the broader construction placed on regulation 12(5) by what Mr Heath described as “Judge Levenson’s interesting decision in SC”. He argued that SC had elided Parliament’s intention to distinguish between (i) those claimants who needed guidance and/or supervision for the purpose of entitlement to the lower rate mobility component and (ii) that much narrower group of claimants who met the much more exacting SMI rules for the higher rate. Mr Heath also referred to the interpretation of similar expressions used in mental health legislation and to the policy objectives underpinning the SMI rules that I had discussed some years ago in a journal article “Severe mental impairment and the higher rate mobility component of DLA” in (1999) 6 Journal of Social Security Law (JSSL) 10-32. 

54.	Both Mr Newington-Bridges and Mr Heath sought to pray in aid Professor Blakemore’s report to support their respective submissions. Mr Newington-Bridges argued that although Professor Blakemore had described the expression “arrested development” as outmoded, applying modern scientific understanding and terminology it could be construed as covering a range of conditions, including functional/cognitive impairment. This in turn could be caused by brain injury (such as the Appellant’s) rather than such impairment being defined by reference to the physical development of the brain. Mr Heath accepted that the expert evidence meant that the simple dichotomy posited in the context of proposition 3 by Mr Commissioner Rice in R(DLA) 2/96 (at paragraph 11) was no longer particularly helpful. His submission was that Professor Blakemore’s report required a more careful investigation of the apparent causes of a claimant’s lack or loss of brain function.

My analysis
55.	I agree with Mr Heath that what I have described as Meaning 1 is the correct way to read regulation 12(5). In other words, for the avoidance of doubt the test is this: does the Appellant suffer from arrested development of the brain or incomplete physical development of the brain? I reach that conclusion for the following four reasons.

56.	First, Mr Commissioner Rice’s underlying assumption in R(DLA) 2/96 that regulation 12(5) was solely concerned with the development (however so defined) of the brain has not been shaken by Professor Blakemore’s expert report. Her evidence certainly demonstrates that the statutory language is hopelessly outdated. It also suggests that the examples given of “arrested development” and “incomplete physical development” respectively in R(DLA) 2/96 are not entirely helpful. That said, Professor Blakemore’s more sophisticated analysis, like R(DLA) 2/96, is predicated throughout on the basis that in applying these terms one is concerned with the functioning of the brain rather than any other organ or part of the body.

57.	Second, despite those reservations, R(DLA) 2/96 is of course a reported decision, whereas SC has not been reported. In addition, and arguably more fundamentally, Judge Levenson’s observations on regulation 12(5) were not actually essential for his decision in SC – in the language of lawyers, they were obiter and not ratio. The basis of the decision in SC (as set out at paragraphs 21-23) was that the tribunal in question (or at least its majority members) had failed to apply the correct statutory test for determining whether a person is unable, or virtually unable, to walk within section 73(1)(a) of the SSCBA 1992. Furthermore, Judge Levenson, when dealing with the alternative possibility that the claimant might qualify under the SMI rules, noted (at paragraph 29) that on the facts of that case the Secretary of State had already conceded that the claimant was severely mentally impaired. The Judge’s observations on the construction of regulation 12(5) were accordingly not necessary to support the decision he had arrived at.

58.	Third, the clear intention of Parliament in introducing the SMI rules, as indeed Mr Newington-Bridges accepted, was to extend eligibility for the higher rate mobility component of DLA to a very small group of claimants (thought to number 8,000-9,000 at the time) who were physically able to walk but whose mental impairment and behavioural problems were so severe that they needed constant supervision and close physical control at all times when out walking. As such, the statutory criteria were very tightly drawn. Judge Levenson’s reading of regulation 12(5), as Judge Lane pointed out when giving permission, had the potential to widen substantially the eligible pool of claimants, which would be inconsistent with the original statutory purpose.

59.	Fourth, I cannot ignore the fact that although the statutory definition of “severe mental impairment” may have been new to the social security scheme in 1992, the phraseology had been borrowed (with some significant redrafting) from long-standing mental health legislation. In that area now concepts such as “mental defectiveness”, “mental deficiency” and “subnormality” have historically been defined by statute by reference to the notion of an “arrested or incomplete development of mind” (see e.g. Mental Deficiency Act 1927, s.1, Mental Health Act 1959, s.4 and Mental Health Act 1983, s.1 (“the 1983 Act”)). Thus section 1(2) of the 1983 Act used to provide that “severe mental impairment” means “a state of arrested or incomplete development of mind which includes severe impairment of intelligence and social functioning and is associated with abnormally aggressive or seriously irresponsible conduct on the part of the person concerned”. These definitions have since been updated, so that section 1(4) of the 1983 Act has now been amended by section 2 of the Mental Health Act 2007 (“the 2007 Act”), such that a “learning disability” is defined as meaning “a state of arrested or incomplete development of the mind which includes significant impairment of intelligence and social functioning.” However, regulation 12(5) was plainly borrowed from section 1 of the 1983 Act before its amendment by the 2007 Act.

60.	Furthermore, regulation 12(5) was deliberately drafted in narrower terms than the mental health legislation (reflecting Parliament’s policy intention, as discussed above) in that its focus was on the development of the brain, not of the mind, and by the insistence that any “incomplete development” must be physical in nature. Thus the phrase “a state of arrested or incomplete development of mind”, taken from the 1983 Act, became “a state of arrested or incomplete physical development of the brain”. However, the syntax of this form of words would necessarily have led to “arrested development” being qualified by the descriptor “physical”, which would have been inconsistent with the then state of medical understanding (as indeed was reflected in R(DLA) 2/96). Thus it was the insertion of the word “physical” between “incomplete” and “development” which then necessitated the addition of “development” after “arrested”, so as to maintain the existing parameters of the definition and to ensure that both aspects of development related to a state “of the brain”. 

61.	I therefore share Judge Lane’s reservations and disagree with Judge Levenson’s approach to the construction of regulation 12(5). That provision does not make a binary distinction between “arrested development” on the one hand and “incomplete physical development of the brain” on the other. Rather, regulation 12(5) applies where the claimant suffers from either arrested development of the brain or incomplete physical development of the brain (in either case with certain consequences). 

62.	It follows that in the present case the Tribunal did not err in law by failing to consider or to apply Judge Levenson’s decision in SC v Secretary of State for Work and Pensions.

Ground 3: the human rights challenge
63.	The human rights arguments were actively canvassed by Dr Harris on the Appellant’s behalf both before the Tribunal and in the initial stages of the further appeal before the Upper Tribunal. Dr Harris’s principal argument was that section 73(3) of the SSCBA 1992, read with regulation 12(5) of the 1991 Regulations, amounted to unlawful indirect discrimination on age grounds, as a claimant had to be younger than 30 in order to qualify for the higher rate mobility component of DLA under the SMI rules.

64.	Although he did not formally abandon this ground of appeal, Mr Newington-Bridges did not elaborate on this basis for challenging the Tribunal’s decision in either his detailed skeleton argument or in his oral submissions. That was doubtless a tactical decision to focus on his strongest points, and in my view a very wise implied concession on his part. Neither the primary nor the secondary legislation includes any formal age limit. Insofar as there was an age 30 cut-off rule, it was laid down by the case law, but R(DLA) 2/96 has now been shown to be wanting in the light of modern advances in medicine and science. Even if indirect age discrimination could be established, the Secretary of State might well be able to make out a strong case for justification, given the original policy objectives underpinning the introduction of the SMI rules. There is also the very real difficulty that the Upper Tribunal has no power to make a declaration of incompatibility as regards primary legislation. 

65.	In all those circumstances I need not consider the human rights challenge any further, and certainly should not be taken as expressing a decided view one way or the other on this ground of appeal.

The Upper Tribunal’s decision on this appeal and the question of disposal
Conclusions: the errors of law in the Tribunal’s decision
66.	Returning to the Tribunal’s statement of reasons in this case, I agree with Mr Newington-Bridges in as much as there are plainly at least two errors of law evident in its decision. The first error of law is that the Tribunal stated a conclusion (“there was not incomplete development of the brain nor arrested development of the brain”, at paragraph 18 of the statement of reasons) but without making sufficient findings of fact to support that conclusion. The second error of law, as already noted, is that the Tribunal, in relying (understandably, and indeed correctly, in view of precedent) on R(DLA) 2/96, had wrongly assumed that as the Appellant was aged over 30 when he suffered the life-changing injuries in the road traffic accident, then he could not under any circumstances qualify for the higher rate mobility component via the SMI route. It follows that the Tribunal’s decision cannot stand.

Disposal of this appeal
67.	Thus as those two errors of law are fundamental, I have no real option but to allow the appeal and so set aside the Tribunal’s decision. There are too many unresolved issues of fact for me to re-make the decision under appeal. It is also more appropriate for the evidence as whole to be evaluated by a new First-tier Tribunal with its range of relevant expertise. The case therefore needs to be re-heard by a new Tribunal. However, simply because this appeal to the Upper Tribunal has succeeded on the law does not necessarily mean that the Appellant will win at the Tribunal re-hearing on the facts. It all depends on the findings of fact that the new Tribunal makes on the evidence before it. I do not doubt the very real problems that the Appellant has in terms of mobility. However, for the reasons that follow, there remain some potentially significant hurdles to be surmounted before concluding that he meets all the rules under the statutory SMI test. Obviously, the new Tribunal will need to consider the evidence systematically in the light of the possible ways in which the Appellant may qualify for the higher rate of the mobility component. It will need to find sufficient facts and give adequate reasons at each stage of its analysis.

Directions to new First-tier Tribunal
The supersession issue
68.	The Appellant’s existing award dates from the earlier Tribunal’s decision of 25 March 2004, awarding the highest rate care component and the lower rate mobility component of DLA, in both instances awarding those components from 5 September 2003 for an indefinite period. The Appellant’s application on 14 September 2009 was technically an application to supersede that appeal tribunal decision. Such a decision can be superseded on the basis that the 2004 tribunal was ignorant of, or mistaken about, a material fact. It can also be superseded on the grounds that there has subsequently been a change of circumstances. It cannot be superseded on the basis of an error of law (Social Security and Child Support (Decisions and Appeals) Regulations 1999 (SI 1999/991), regulation 6(2)(a)-(c)).

69.	It is not easy to see how the 2004 Tribunal was ignorant of, or mistaken about, a material fact.  However, the new Tribunal may well take the view that the death of the Appellant’s step-father in January 2009 was a relevant change of circumstances that led to a deterioration in the Appellant’s condition and an increase in his care and mobility needs. The question then, once potential grounds for a supersession have been established, is whether on the facts the Appellant satisfies the SMI rules.

The standard test: Is the Appellant virtually unable to walk?
70.	The first question which the Tribunal should consider is whether the Appellant qualifies for higher rate mobility on the basis of the usual test, i.e. is he “virtually unable to walk” within section 73(1)(a) of the SSCBA 1992 and regulation 12(1)(a)(ii) of the 1991 Regulations? At first sight this question might appear to admit of only one answer (namely, in the negative), given the evidence there is on file as to the Appellant’s ability to walk some distance outdoors, e.g. across countryside terrain (indeed, on at least one occasion a police helicopter had to be called into to search for him when he went missing). However, regulation 12(1)(a)(ii) requires the Tribunal to have regard to “his physical condition as a whole”, and specifically the various factors listed there. There is certainly some evidence of the Appellant’s tendency to stumble. The previous Tribunal’s record of proceedings noted Dr Harris’s submission at the hearing that as regards the “concept of virtually unable to walk, it’s the manner we contend renders him virtually unable to walk in the accepted sense” (emphasis in the original). The last Tribunal failed to make findings of fact or give adequate reasons on all the relevant matters under regulation 12, when that point had been put in issue, which amounts to a further error of law on its part. 

71.	The new Tribunal will accordingly need to make appropriate findings of fact as to the “distance over which or the speed at which or the length of time for which or the manner in which he can make progress on foot without severe discomfort” before explaining its overall assessment on whether or not the Appellant is “virtually unable to walk” . The new Tribunal may decide that, insofar as the Appellant undoubtedly has difficulties when out walking, these are matters which go to his entitlement to the lower rate mobility component under section 73(1)(d) (subject to any overriding entitlement to the higher rate under the SMI rules), but that is a matter for the new panel to determine. If the new Tribunal concludes that section 73(1)(a) (the “virtually unable to walk” test) is not satisfied, then it will have to turn to consider the various requirements under the SMI rules.

The SMI rules: (1) is the Appellant severely mentally impaired?
72.	The first question in this context is whether the Appellant is “severely mentally impaired”. There are actually two requirements laid down by regulation 12(5). The first is whether he suffers from “a state of arrested development or incomplete physical development of the brain”; the second is whether this condition “results in severe impairment of intelligence and social functioning”.

“a state of arrested development or incomplete physical development of the brain...”
73.	The first limb of regulation 12(5) must now be interpreted and applied in the light of the findings above and in view of Professor Blakemore’s expert evidence. The statutory phraseology harks back to an earlier age when the state of scientific knowledge was much more rudimentary than today. Unlike the mental health legislation, there has been no attempt to bring the legislative language into line with modern scientific understanding and terminology. We therefore have to do the best we can with the tools available.

74.	As to the first alternative in the first limb of regulation 12(5), the question is whether the Appellant suffers from a “state of arrested development ... of the brain”. Professor Blakemore’s report shows that the umbrella term “arrested development” encompasses “‘developmental regression”, “functional/cognitive impairment” and “developmental delay”. There is no evidence to suggest that the Appellant falls into the first or last of those categories. However, the new Tribunal may well find as a fact that he has experienced very considerable functional/cognitive impairment. If so, that can be “a state of arrested development ... of the brain.” I accept Mr Heath’s point that there was no evidence that the Appellant suffered from “a state of arrested development” before his RTA. With respect, however, that is not the point. The question is not how he was when he was 30, before the accident, but how he is now when he is 48 (or, technically, how he was at the age of 43 at the date of the decision under appeal). I acknowledge that this type of case was not within the contemplation of those responsible for framing the 1991 Regulations – but those words must now be construed and applied in the light of modern scientific knowledge.

75.	If the new Tribunal finds that the Appellant does not suffer from a “state of arrested development ... of the brain”, it must then turn to consider the alternative possibility, namely that he suffers from “a state of ... incomplete physical development of the brain”. In doing so, the Tribunal must abandon any adherence to the straightforward age 30 cut-off rule based on R(DLA) 2/96. As noted above, Professor Blakemore’s evidence was that “the brain will have ceased developing, in terms of experience-expectant changes in grey matter and white matter, by the thirties or early forties in most people”. On that basis alone, and applying the balance of probabilities, the new Tribunal might conclude that the Appellant suffers from “a state of ... incomplete physical development of the brain”. Again, I accept Mr Heath’s point that there was no evidence of “incomplete physical development of the brain” before the RTA. However, for the same reason as identified above, that is not the point. I also accept Mr Heath’s submission that the accident itself did not directly cause any “incomplete physical development of the brain”. But the legislation does not seek to define entitlement in terms of causation, at least in that respect; rather, the focus is on a state of medical fact. 

76.	All that said, it seems to me that if the new Tribunal is going to find that the Appellant meets the test in the first limb of regulation 12(5), the more natural basis for such a finding would be “arrested development” rather than “incomplete physical development of the brain”. I make that suggestion as the remainder of regulation 12(5) does bring into play a causation requirement: the state of arrested development or incomplete physical development of the brain must be one which “results in severe impairment of intelligence and social functioning”. It may well be that as a matter of medical science the Appellant’s brain was not fully physically developed at the age of 32. However, it is hard to see how that incomplete development in itself gave rise to the required consequence of a severe impairment of intelligence and social functioning. That notion fits far better with a finding of arrested development of the brain. This takes us to the next element of the SMI rules.

“... which results in severe impairment of intelligence and social functioning”
77.	The Tribunal made no findings as to this second aspect of regulation 12(5), having found that the appeal fell at the first hurdle. On the documentary evidence on file, and assuming it finds the first limb of regulation 12(5) to be satisfied, the new Tribunal may perhaps need little persuading that the Appellant’s condition amounts to “severe impairment of ... social functioning”.

78.	The statutory test, however, is that the severe mental impairment must result in “severe impairment of intelligence and social functioning”. Does the Appellant have severe impairment of intelligence? The EMP report, in its account of a typical day, noted that the Appellant “tends to read the papers, do crosswords or watch TV”. I have also had the advantage of reading an extremely detailed and much more recent report prepared under the supervision of a consultant neuropsychologist (dated 5 July 2013). This was obviously not before the previous Tribunal. The new Tribunal is entitled to take that report into account, so long as it is satisfied that it is broadly representative of the Appellant’s condition in September 2009. The 2013 consultant neuropsychologist’s report stated that his “ability to understand written words is better than his ability to understand spoken words”. Taken in isolation, those sorts of observations might imply that the Appellant has not actually suffered “severe impairment of intelligence”. However, the evidence is also that he can remember little or none of such material only a matter of minutes later, and so assessing the effect of the Appellant’s injuries on his intelligence is not a straightforward matter.

79.	In this context the Court of Appeal’s decision in M (a child) v Chief Adjudication Officer (reported as R(DLA) 1/00) is authority for two propositions. The first is that a claimant must establish both severe impairment of intelligence and severe impairment of social functioning. The second is that a standard IQ intelligence test alone should not be regarded as a definitive measure of whether an individual has severe impairment of intelligence. This overruled earlier Commissioners’ case law to the effect that only people with an IQ of 55 or below were regarded as having severely impaired intelligence (e.g. CDLA/1698/1997). According to Simon Brown LJ, giving the leading judgment in the Court of Appeal in M (a child), “amongst the dictionary definitions of intelligence one finds reference not merely to the functions of understanding and intellect but also to the qualities of insight and sagacity”. Thus:

“I conclude that whilst in every case the claimant's IQ as conventionally tested is likely to be the essential starting point for considering the impairment of intelligence, and whilst it is perfectly reasonable to take an IQ of 55 or less as the prima facie touchstone of severe impairment, that test and that score will not invariably prove decisive. Rather it should be recognised that an IQ result may give a misleading impression of the claimant's useful intelligence and that in some cases at least an impairment of social functioning will shade into an impairment of intelligence. Tribunals and Commissioners will accordingly need to admit and consider evidence other than a mere IQ score.”

80.	I note also that in CD v Secretary of State for Work and Pensions [2013] UKUT 068 (AAC), Judge Bano held that regulation 12(5) requires:

“an evaluation of a claimant’s ‘useful intelligence’, including what the Court of Appeal in R(DLA) 2/00 called “insight and sagacity”. Mrs Dean, on behalf of the Secretary of State has in my view helpfully and accurately equated those qualities to “the ability to function in real-life situations”, and I agree with her that in order to assess that ability the tribunal ought to have taken into account the very considerable body of evidence in this case concerning the claimant’s lack of sense of danger.”

81.	In the present case, although it is a matter for the new Tribunal, there appears to be ample evidence of the Appellant’s lack of any sense of danger in real-life situations. For example, his GP reported that he had “absolutely no appreciation of danger and seems oblivious of injury when he sustains it” (letter dated 18 November 2009). Thus the simple fact that the Appellant can read and do crosswords does not necessarily preclude him from suffering from severe impairment of intelligence and social functioning, looking at both those matters in the round.

82.	If both limbs of regulation 12(5) are met, and so the Appellant is found to be severely mentally impaired within section 73(3)(a), the new Tribunal must then go on to consider whether the terms of section 73(3)(b) and regulation 12(6) are met.

The SMI rules (2): does the Appellant display severe behavioural problems?
83.	In his skeleton argument (at paragraph 31), Mr Newington-Bridges asserts that this requirement under section 73(3)(b) is not in dispute in the present case. I disagree. The DWP in its initial decision-making process did not feel it necessary to express a view (see paragraph 8 above). The Tribunal recognised it as a live issue but then made no findings on the point (presumably on the basis that it was unnecessary to do so, given its conclusion on section 73(3)(a)). Mr Heath, in his skeleton argument, regarded the matter as still open on the facts (at paragraph 23(2)).

84.	My preliminary reading of the documentary evidence is that the Appellant undoubtedly displays some behavioural problems, and there seems little doubt that these have increased since the death of his step-father in early 2009 (and, of course, the application for supersession was made later that same year). The question for the new Tribunal, however, is a rather different one, namely whether at the material time (September 2009) the Appellant displayed severe behavioural problems, as that term is comprehensively and exhaustively defined by regulation 12(6) of the 1991 Regulations:

	“(6) A person falls within subsection (3)(b) of section 73 of the Act (severe behavioural problems) if he exhibits disruptive behaviour which–
		(a) is extreme,
	(b) regularly requires another person to intervene and physically restrain him in order to prevent him causing physical injury to himself or another, or damage to property, and
(c) is so unpredictable that he requires another person to be present and watching over him whenever he is awake.”

85.	The three conditions set out in regulation 12(6)(a) to (c) are demanding and cumulative. The mere fact that the Appellant needs continual (or possibly even continuous) supervision does not necessarily mean that these three conditions are satisfied. I considered the proper approach to these various terms in some detail in MG v Secretary of State for Work and Pensions [2012] UKUT 429 (AAC) (at paragraphs 22-39) and will not repeat that analysis here.

86.	So, on my initial reading of the evidence, the question as to whether at the material time the Appellant displayed severe behavioural problems within those narrowly-defined terms is very much moot. For example, the GP in her letter of 18 November 2009 referred to “emotional lability with occasional aggressive outbursts”, which on the face of it (at least in terms of frequency) may fall some way short of the requirements of regulation 12(6)(b). The EMP report included an account of a typical day which does not suggest that the high threshold set by regulation 12(6) is met. The EMP also reported that the Appellant was not destructive to property or to others. Dr Harris made detailed critical comments on the findings of the EMP report (see p.188 of the bundle), but again not in a way which would suggest that regulation 12(6) came into play. On the other hand, one of Dr Harris’s detailed submissions to the previous Tribunal did refer to the Appellant’s “explosive outbursts of temper” (p.109). The consultant neuropsychologist’s report from July 2013 (see paragraph 78 above) characterises the principal disabling condition as global amnesia, and again arguably there is little on the face of that report to suggest that regulation 12(6) may apply in the present case.

87.	I emphasise that I have not reached a concluded view on this issue. It would be wrong for me to do so, not having had the advantage of hearing detailed oral evidence and submissions on the point. It is, however, only fair for me to highlight the issues that the Appellant’s representatives need to address in this respect. In other words, even if he gets home on “severely mentally impaired” under section 73(3)(a) and regulation 12(5), it is by no means certain that he will also meet the additional requirement as regards “severe behavioural problems” under section 73(3)(b) and regulation 12(6). In compiling their case, the Appellant’s representatives should consider with some care the guidance contained in MG v Secretary of State for Work and Pensions as regards these criteria.

The SMI rules (3): does the Appellant qualify for highest rate care component?
88.	This is straightforward. The third requirement under the SMI rules, namely that the claimant qualifies for the highest rate care component, is not in dispute here.

Other preparation for the new hearing
89.	In the light of the range and complexity of the issues highlighted above, the Secretary of State’s representative should prepare a supplementary submission for the new Tribunal with a view to helping the Tribunal to focus on the precise points which are at issue between the parties. The supplementary submission should address each of the following questions in turn, giving reasons in each instance for the position taken. This will also assist those representing the Appellant to prepare his case. In particular, does the Secretary of State accept that the Appellant:

(a)	suffers from a state of arrested development of the brain?
(b)	alternatively suffers from a state of incomplete physical development of the brain?
(c)	suffers from a condition (whether (a) and/or (b)) which leads to severe impairment of intelligence and social functioning?
(d)	exhibits disruptive behaviour which is extreme?
(e)	exhibits disruptive behaviour which regularly requires another person to intervene and physically restrain him in order to prevent him causing physical injury to himself or another, or damage to property?
(f)	exhibits disruptive behaviour which is so unpredictable that he requires another person to be present and watching over him whenever he is awake?
(g)	satisfies both the day and night time conditions for the award of the highest rate care component?

Personal Independence Payment
90.	People of working age can no longer make new claims for DLA. People of working age who have existing DLA awards are in the (slow) process of being transferred to the new benefit Personal Independence Payment (PIP). There are various ways in which a person may get 12 points for mobility activities under the PIP scheme and so qualify for the “enhanced” rate of the PIP mobility component (equivalent in cash terms to the higher rate mobility component of DLA). One of those ways is if the claimant “cannot follow the route of a familiar journey without another person, an assistance dog or an orientation aid”. The Appellant may well meet that condition, given the evidence that he cannot find his way back from the post-box 600 metres from his home. However, that does not mean that the Appellant can claim PIP now. The rules governing transfers of awards from DLA to PIP are complex and do not yet apply to all parts of the country. It may well be that the Appellant will not be able to make a claim for PIP until 2015 (or possibly later; see https://www.gov.uk/pip-checker). A Citizens Advice Bureau should be able to give detailed advice on the prospects of making a PIP claim.

Conclusion
91.	For the reasons explained above, the Tribunal’s decision involves an error of law. I therefore allow the appeal and set aside the decision of the tribunal (Tribunals Courts and Enforcement Act 2007, section 12(2)(a)). The case is remitted for rehearing by a new First-tier Tribunal subject to the directions and guidance above (section 12(2)(b)(i)).  

Signed on the original				Nicholas Wikeley
on 08 July 2014						Judge of the Upper Tribunal