Neutral Citation Number: [2008] EWCA Crim 922
Case No: 200800837
IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CRIMINAL DIVISION)
ON APPEAL FROM CROWN COURT WOOLWICH
THE HONOURABLE MR JUSTICE PITCHFORD
T20087038
Royal Courts of Justice
Strand, London, WC2A 2LL

Date: 29/04/2008
Before :

LORD JUSTICE RIX
MR JUSTICE HENRIQUES
and
SIR RICHARD CURTIS
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Between :

	G	Appellant	
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	Regina	Respondent	

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Mr I Leist (instructed by Sonia Lawrence Smith Partnership) for the Appellant
Mr D Perry QC, Mr William Hays (instructed by Crown Prosecution Service) for the Crown

Hearing dates : 2nd April 2008
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Judgment
This is the judgment of the court :
1.	This is an appeal pursued by a defendant awaiting trial, G, who stands charged with two counts of terrorism. The appeal arises under section 35 of the Criminal Procedure and Investigations Act 1996 (the “1996 Act”) following a preparatory hearing. 
2.	The two counts of terrorism are respectively under section 5(1) of the Terrorism Act 2006 (the “2006 Act”) and section 58 of the Terrorism Act 2000 (the 2000 Act”). The first count, under the 2006 Act, alleges that between 13 April 2006 and 3 February 2007 G was preparing to commit acts of terrorism. The second count, under the 2006 Act, alleges that between 27 January 2005 and 3 February 2007 G collected information of a kind that was likely to be useful to a terrorist. 
3.	On 18 January 2008 Calvert Smith J ordered a preparatory hearing under the 1996 Act to resolve whether evidence about G’s mental illness and G’s motivations in the light of it were capable of amounting in law to a defence under section 58(3) of the 2000 Act. The prosecution accepted that it could do so for the purpose of the count under section 5(1) of the 2006 Act but disputed the position under section 58 of the 2000 Act. 
4.	The preparatory hearing was heard by Pitchford J (the “judge”) on 8 February 2008. He held that G had no defence of “reasonable excuse” under section 58(3) of the 2000 Act. The judge gave leave to appeal. A few days later, on 13 February 2008 this court handed down a reserved judgment in R v. K [2008] EWCA Crim 185 in the course of which Lord Phillips of Worth Matravers CJ, giving the judgment of the court, held that bad or even seriously criminal conduct could amount to a “reasonable excuse” for the purposes of section 58(3) as long as a defendant’s possession of documents or records was for a purpose other than to assist in the commission or preparation of an act of terrorism. In the circumstances the Crown now concedes on this appeal that K provides G with a potential defence of reasonable excuse under section 58(3) of the 2000 Act, but submits that K is not binding on this court and is in any event per incuriam  and wrong.
5.	In effect, therefore, the Crown, which is the respondent to this appeal, has accepted that in the light of K the forensic burden falls on it to explain why this appeal should not be allowed.
6.	In our judgment the Crown failed in that burden, as we determined at the time of the hearing. We therefore allowed G’s appeal, but reserved our reasons, which are now contained in this judgment.
The background facts
7.	On 28 January 2005 the appellant was sentenced, in respect of a number of non-terrorist offences, to detention in a young offender institution for a period of 3½ years. He was born on 21 August 1985, so that he was then 19, and is now 22. On 25 October 2006, after he had turned 21, he was transferred to an adult prison. During his time in detention, he had converted to Islam. 
8.	As for the current proceedings against him, the prosecution case is that while in custody the appellant collected and recorded information likely to be of use to a person committing or preparing an act of terrorism. The items collected by him include a chemical formula for producing hydrogen chloride, plans for making bombs including a diagram of a pipe bomb, and various text books on explosives. He made notes on how explosives could be manufactured and used. He also drew accurate maps of the Territorial Army Centre in Chesterfield and identified the location of the armoury there. There was also material containing his observations on the waging of jihad in Great Britain. These items were found during repeated searches of the appellant’s cell accommodation: on 4 April 2006 and 10 August 2006 (at HMYOI Stoke Heath), and on 30 December 2006 and 23 January 2007 (at HMP Featherstone). 
9.	On 2 February 2007 the appellant was arrested and interviewed under caution. In summary, his explanation for collecting and recording the information was that he wanted to “wind up” the prison staff because they were provoking him. He said: “…so I wanted to wind them up and I know how this terrorism stuff…really gets on their nerves…” He said that he left the material in his cell to be found. After two interviews the appellant was assessed to be unfit for further questioning. 
10.	On 12 June 2007, the appellant was admitted to Ashworth Hospital under the Mental Health Act 1983.
11.	In a psychiatric court report dated 7 November 2007, Dr Qurashi, a consultant forensic psychiatrist, concluded that the appellant is suffering from a severe and enduring mental illness, namely paranoid schizophrenia, which had been previously undiagnosed and untreated. It is accepted by the Crown that in Dr Qurashi’s opinion the appellant collected and recorded the information in question, now the subject of prosecution, as a direct consequence of his illness. In his report Dr Qurashi had said this (at para 14.9):

“In summary G’s account of the various documents found in his cell whilst on remand was to “wind up” prison officers. He has consistently reported that he had no intention of committing acts of terrorism. When asked why he felt the need to antagonise prison officers he believes that [they] were “whispering” about him. This is highly likely to be a psychotic experience, namely an auditory hallucination.”

12.	In his ruling the judge set out a significant passage in Dr Qurashi’s supplementary report dated 17 December 2007, in part as follows:

“1. Comment on whether G’s criminal behaviour is a direct consequence of his illness?

It is my opinion that G’s alleged criminal behaviour, in terms of generating the written material, was indeed a direct consequence of an untreated, severe psychotic illness. As I have stated in my court report, at paragraph 14.9, dated 7th November 2007, G’s reasons for generating the written material were based on psychotic, deluded reasons. He firmly believed that prison officers were provoking him in an attempt to antagonise him by, for example, standing at his cell door whispering throughout the night. In my experience G is describing an auditory hallucination. He also believed prison officers were “out to get him and kick him” (at paragraph 8.54). This is a paranoid persecutory delusion. G reports that his response was to “provoke” the prison officers who he believed were intentionally provoking him. Therefore, if G had not experienced these psychotic experiences within the prison estate he would not, in my opinion, have generated the offending materials…

During his time in prison he is described as being a disruptive prisoner. It is well recognised that individuals experiencing a severe, untreated psychotic illness are described, by lay individuals, as being agitated, aroused, uncooperative and disruptive. A severe psychosis not only affects thoughts but also mood, perceptions (of self, others and the environment) and consequent behaviour. His presentation in prison, while untreated, is to be contrasted with his presentation when treated. I have had the benefit of observing him and assessing him, with members of the multidisciplinary team, in both states. When unmedicated he is provocative, antagonistic, intimidating, verbally abusive, disinhibited, demanding, suicidal, suspicious and, of note, other patients complained of G “winding them up”. When provided with treatment G is an amenable, co-operative individual (paragraphs 11.6-11.33).”

The statutory regime
13.	Section 1 of the Terrorism Act 2000 defines terrorism:

“1(1) In this Act “terrorism” means the use or threat of action where – 
(a)	the action falls within subsection (2), 
(b)	the use or threat is designed to influence the government or to intimidate the public or a section of the public, and
(c)	the use or threat is made for the purpose of advancing a political, religious or ideological cause.

Subsection (2) describes action involving various serious consequences, such as serious violence against a person or serious damage to property. 
14.	Section 58 (headed “Collection of information”) describes the offence which is the subject-matter of this appeal and provides:

	“58 (1) A person commits an offence if –
(a)	he collects or makes a record of information of a kind likely to be useful to a person committing or preparing an act of terrorism, or
(b)	he possesses a document or record containing information of that kind…

(3) It is a defence for a person charged with an offence under this section to prove that he had a reasonable excuse for his action or possession.”
15.	The defence of reasonable excuse under section 58(3) is at the heart of the judge’s ruling, in the first paragraph of which he said:
“I am asked to rule whether the defendant’s mental illness is capable in law of constituting a reasonable excuse for collecting information contrary to section 58(1) of the Terrorism Act 2000.” 
16.	In the light of K (and of another decision of the same constitution of this court handed down at the same time, R v. Zafar [2008] EWCA Crim 184) the Crown submits that the true construction of section 58 of the 2000 Act has to be considered together with section 57 of the same Act, which concerns the offence of “Possession for terrorist purposes”, and provides:

“57 (1) A person commits an offence if he possesses an article in circumstances which give rise to a reasonable suspicion that his possession is for a purpose connected with the commission, preparation or instigation of an act of terrorism.

(2) It is a defence for a person charged with an offence under this section to prove that his possession of the article was not for a purpose connected with the commission, preparation or instigation of an act of terrorism.”

G is not charged with an offence under section 57. 
17.	Section 118 of the 2000 Act (headed “Defences”) provides:
“118 (1) Subsection (2) applies where in accordance with a provision mentioned in subsection (5) it is a defence for a person charged with a defence to prove a particular matter.

(2) If the person adduces evidence which is sufficient to raise an issue with respect to the matter the court or jury shall assume that the defence is satisfied unless the prosecution proves beyond reasonable doubt that it is not.”

Subsection (5) mentions inter alia sections 57 and 58. Thus section 118(2) applies to the defences stated in sections 57(2) and 58(3).
18.	Section 5(1) of the 2006 Act, headed “Preparation of terrorist acts”, an offence under which G is also charged but which is not the subject-matter of the judge’s ruling, provides:

	“5 (1) A person commits an offence if, with the intention of –
(a)	committing an act of terrorism, or
(b)	assisting an another to commit such acts,
he engages in any conduct in preparation for giving effect to his intention.”

The ruling
19.	Before the judge, the Crown’s position was stated in its skeleton argument dated 25 January 2008 as follows: 

“The defence as set out in his interviews and in his Defence Statement is that he was not preparing or intent on any terrorist acts (count 1) and he had possession or collected the material with the purpose to “be disruptive and to provoke the prison staff” (count 2)…It is conceded that his mental state and his stated defence are matters that a jury would be entitled to consider in respect of count 1. He must be proved to have had the intention to commit an act of terrorism or to assist another to commit an act. However in respect of count 2 it is submitted that the evidence of his mental state and his declared defence affords no defence in law and is not therefore admissible in respect of that count.”

That submission was developed by reference to decisions where the courts had ruled on what might or might not amount to a reasonable excuse. It was accepted that such situations might be fact specific. It was submitted that in the present case G’s defence “amounts to no more than an explanation and not an excuse or if it may amount to an excuse that no reasonable man would think it properly excusable and therefore reasonable.” Only “truly innocent” possession could go unpunished, such as that in the hands of a journalist or for the purposes of legitimate academic study. The reasonable excuse defence should be a narrow one. 
20.	There was nothing in that skeleton to refute reliance on the medical evidence as a matter of causation (other than an observation that it did not amount to evidence of insanity or automatism). It was conceded that the medical evidence was relevant to the jury’s decision on section 5(1) of the 2006 Act (count 1). However, given the narrow interpretation to be given to section 58(3), the medical evidence simply was not relevant to count 2.   
21.	In its skeleton argument in response dated 4 February 2008, the defence did not appear to submit that the Crown’s contention was wrong in principle, but that the medical evidence could turn what might otherwise be an unreasonable excuse into a reasonable one. Thus –
“it is submitted that a reasonable man might consider [G’s] winding up of prison officers by collecting material is properly excusable and therefore a reasonable excuse, because it was a direct consequence of his illness.”

In response to that, it appears to have been only at the preparatory hearing itself that the Crown expanded its argument to say that G’s medical illness did not cause his conduct. 
22.	In the result two points appear to have been presented to the judge, one relating to the width of the section 58(3) defence as a matter of law, the second being a point of causation. These two points are reflected in the judge’s ruling (see below). It seems, however, that defence opposition on the first point may have been muted. 
23.	The judge recognised that Dr Qurashi’s reports provided evidence that G’s conduct was caused by his illness. He said (at 4G of the transcript of the ruling): “Thus it is Dr Qurashi’s view that [G’s] collection of the information was also caused by the illness.” He also said (at 7B), immediately after citing from Dr Qurashi’s supplementary report: “…Dr Qurashi expresses the firm view both as to causation of the delusion to which he referred and as to causation of a wish to provoke the prison officers.” Nevertheless, the judge concluded that G’s mental illness “is not capable of constituting a reasonable excuse” under section 58(3), and to have done so because there was no sufficient causal connection between the illness and G’s conduct (at 11E/G). How was that?
24.	As for the two separate points before the judge, the first was whether the purpose of winding up the prison staff was capable of being a reasonable excuse for the collection of the material. To that question, reflecting the Crown’s argument, the judge answered, No, and possibly did so, it seems, without dispute. He said (at 9F-10D):

“Here it seems to me that just because a defendant has a purpose for the collection of section 58 information other than the assistance of terrorism does not necessarily provide him with an excuse since the section requires no particular intention. Nor does the section require any degree of likelihood that the information will fall into the possession of a terrorist. Its purpose is to prohibit a collection which, objectively viewed, would be useful to a terrorist if it came into the possession of a terrorist. However, I can envisage the presence of a reasonable excuse when material is collected for academic research or when the defendant did not realise on reasonable grounds that the information may assist a terrorist.

I do not understand it to be disputed by the defence, and I agree with the prosecution, that the collection of this information for the purpose of making mischief with prison staff is not capable of excusing the collection. It may have been a reason for the collection, but it was not an admissible excuse for it. The reason why I reach that view is that upon the defendant’s own account, he deliberately collected information of this quality because he wanted to wind up the prison staff.”
25.	It seems from that passage of the judge’s ruling that an illegitimate reason cannot amount to a reasonable excuse. We shall call that the “illegitimate reason” point.
26.	The second point was one of causation, because of the medical evidence that what caused G to act in the way that he did was his mental illness. That may ultimately have been the real point of dispute argued below. We shall call it the “causation” point. However, the two points became somewhat unified in the judge’s formulation of the issue before him in the very first paragraph of his ruling (at 2C):

“I am asked to rule whether the defendant’s mental illness is capable in law of constituting a reasonable excuse for collecting information contrary to section 58(1) of the Terrorism Act 2000.”
27.	On this point, the judge accepted the Crown’s submission that “there is no evidence that the mental illness caused the prohibited act…only that its delusions created the occasion for the prohibited and deliberate response” (at 11B). The judge reasoned (at 11D/G):

“Mr Leist on behalf of the defendant argues, relying on the decision of the House of Lords in Wang…that I should leave to the jury the question whether there is a sufficient connection between the mental illness and the collection of information to render the mental illness a reasonable excuse. In my judgment, for the reasons advanced on behalf of the prosecution, Mr G’s mental illness is not capable of constituting a reasonable excuse to the charge under section 58 of the Terrorism Act 2000. The reason it is not is that it does not affect [G’s] ability to make a choice whether or not to respond as he did to the circumstances as he believed them to be.”
28.	In the light now of R v. K the position has now been reversed. Whereas the causation point appears to have been the essential point argued below, on this appeal, in the light of K, it is the illegitimate reason point which has been put in the forefront of the argument on behalf of G. Nevertheless, the causation point cannot be overlooked. Perhaps, after all, they are intertwined. 
R v. K
29.	In K, the appellant, K, was charged under section 58(1) with the possession of documents concerning the formation and organisation of jihadist movements. At a preparatory hearing K submitted that section 58 was insufficiently certain to comply with the doctrine of legality either at common law or under article 7 of the European Convention of Human Rights. The argument was that the words “likely to be of use to” were so broad and undefined as to criminalise myriad items of legitimate material. 
30.	The Crown submitted, in answer to the court’s enquiry, that section 58 was intended to cover information of any kind, whether or not on its face it would raise a reasonable suspicion that it might be intended to be used for the commission or preparation of an act of terrorism, provided it could be proved by extrinsic evidence that the person charged with possessing it intended it to be used for the commission of an act of terrorism. Thus an A to Z could fall within the scope of the section. The court also raised questions about the section 58(3) defence of reasonable excuse. The Crown’s submission in this connection was that only a lawful purpose for possessing the information could provide a reasonable excuse.   
31.	The court rejected these submissions, having considered section 58 of the 2000 Act in the light of provisions of section 2 of the 2006 Act. It concluded:

“13…We consider that it is plain from the language of section 58 that it covers only documents that fall within the description in (3)(b) [of section 2]. A document or record will only fall within section 58 if it is of a kind that is likely to provide practical assistance to a person committing or preparing an act of terrorism. A document that simply encourages the commission of acts of terrorism does not fall within section 58.
  
14. The provisions of section 2 of the 2006 Act, and in particular those of section 2(5), require the jury to have regard to surrounding circumstances when deciding whether a publication is likely to be useful in the commission or preparation of acts of terrorism. Contrary to Mr Sharp’s submission, we do not consider that the same is true of section 58 of the 2000 Act. The natural meaning of that section requires that a document or record that infringes it must contain information of such a nature as to raise a reasonable suspicion that it is intended to be used to assist in the preparation or commission of an act of terrorism. It must be information that calls for an explanation. Thus the section places on the person possessing it the obligation to provide a reasonable excuse. Extrinsic evidence may be adduced to explain the nature of the information...What is not legitimate under section 58 is to seek to demonstrate, by reference to extrinsic evidence, that a document, innocuous on its face, is intended to be used for the purpose of committing or preparing a terrorist act. 

15. As for the nature of ‘reasonable excuse’, it seems to us that this is simply an explanation that the document or record is possessed for a purpose other than to assist in the commission or preparation of an act of terrorism. It matters not that that other purpose may infringe some other provision of the criminal or civil code. 

16. If section 58 is interpreted in accordance with this judgment, its effect will not be so uncertain as to offend against the doctrine of legality…”
32.	Paragraph 15 of that reasoning has to be understood in the light also of paragraph 10, where Lord Phillips said:

“As to the question of what constituted a reasonable excuse, Mr Sharp submitted that this meant a purpose for possessing the information that was lawful. We asked Mr Sharp whether this meant that a defendant could properly be convicted under section 58 if he explained that he possessed information as to how to make explosives for the purpose of committing a bank robbery. Mr Sharp had no ready answer to that question.” 
33.	This court in K was therefore able to uphold the ruling made in the preparatory hearing in that case, which had also been to reject the submission that the statute was too uncertain to meet the doctrine of legality. 
34.	On the basis of this reasoning, it is submitted by Mr Leist on behalf of G that the judge was wrong to have said, even if encouraged at that time to do so by lack of determined opposition on his part, that the collecting of information for the purpose of winding up of the prison staff was not a reasonable excuse. He says that a reasonable excuse is simply an explanation that information “is possessed for a purpose other than to assist in the commission or preparation of an act of terrorism” (K at para 15). It is an explanation, where it is needed, that rebuts the “reasonable suspicion that it [the information in question] is intended to be used to assist in the preparation or commission of an act of terrorism” (K at para 14). In that context, G’s mental illness is simply further, albeit important and objectively independent, evidence in support of G’s case that he collected and possessed the material in question for a purpose other than to assist in the commission or preparation of an act of terrorism.  
The submissions of the Crown
35.	On behalf of the Crown, Mr David Perry QC, in his wide-ranging skeleton argument dated 26 March 2008, accepts that the judge’s reasoning in his ruling (on what we have called the illegitimate reason point) is inconsistent with the decision in K, but submits that jurisprudence in relation to section 58 and its differences from section 57 has become the subject of disarray: and that in these circumstances this court should regard what was said about section 58 in K as not binding on it, either because it was obiter or per incuriam or both. 
36.	In brief, Mr Perry submits that this court erred in K in interpreting section 58 as incorporating the requirement found in section 57, but not in section 58, that the information in question should “give rise to a reasonable suspicion that his possession is for a purpose connected with the commission, preparation or instigation of an act of terrorism” (see section 57(1) from which that language is quoted, and see also K at para 14 where it is stated that the material under section 58(1) “must contain information of such a nature as to raise a reasonable suspicion that it is intended to be used to assist in the preparation or commission of an act of terrorism”). This was in effect to turn the section 58 offence into an offence requiring specific intent, which is how the language of section 57(1) had been interpreted in R v. Rowe [2007] EWCA Crim 635, [2007] QB 975. 
37.	In Rowe a constitution of this court comprising five judges presided over by Lord Phillips CJ had considered sections 57 and 58 and what a previous decision had said about them in R v. M [2007] EWCA Crim 218. In M this court had held, on an appeal arising from a preparatory ruling, that electronically stored data was not an “article” within section 57(1), as distinct from “a record of information” or “a document or record” within section 58(1). Otherwise, the court in M would have had difficulties in distinguishing the two sections, but as it was “Section 58 is not redundant” (at para 36). Rowe held that the decision in M had been reached per incuriam (applying R v. Simpson [2003] EWCA Crim 1499, [2004] QB 118) and therefore did not follow it. In the course of his judgment in Rowe Lord Phillips said this about the distinction between the two sections:

“34. There is undoubtedly an overlap between sections 57 and 58, but it is not correct to suggest that if documents and records constitute articles for the purpose of section 57, section 58 is almost superfluous. Collecting information, which falls within section 58 alone, may well not involve making a record of the information. Equally, a person who possesses information likely to be useful to a person committing or preparing an act of terrorism may well not be in possession of it for a purpose connected with the commission, preparation or instigation of an act of terrorism. 

35. Sections 57 and 58 are indeed dealing with different aspects of activities relating to terrorism. Section 57 is dealing with possessing articles for the purpose of terrorist acts. Section 58 is dealing with collecting or holding information that is of a kind likely to be useful to those involved in acts of terrorism. Section 57 includes a specific intention, section 58 does not.”
38.	In R v. Zafar, which the constitution of this court which decided K (Lord Phillips CJ, Owen and Bean JJ) also decided on the same day, the appeal arose out of convictions under section 57. The articles in question were computer discs which stored literature of an extremist nature. This court quashed the convictions on the ground that the trial judge had failed to direct the jury that they had to be satisfied that each appellant had intended to use the relevant articles to incite his fellow planners to fight in Afghanistan. It held that section 57 was to be interpreted in such a way as to require a direct connection between the article possessed and the prospective act of terrorism. Lord Phillips said (at para 29) that –

	“The section should be interpreted as if it reads:

“A person commits an offence if he possesses an article in circumstances which give rise to a reasonable suspicion that he intends it to be used for the purpose of the commission, preparation or instigation of an act of terrorism.””
39.	Mr Perry submits that in K this court, by inserting into section 58(1) the language found in section 57(1), language which in Zafar it interpreted as requiring the intent there defined, was removing the essential distinction between the two sections (accepted in Rowe), whereby section 57 concerned an offence of specific intent and section 58 did not. But, he submits, the distinction between the two sections should be marked and maintained. In section 57, possession of the article in question must give rise to a reasonable suspicion that the article is possessed for a terrorist purpose, but it is a defence to show that the article was not possessed for a terrorist purpose. In section 58, the information in question must be of a kind likely to be useful to a person committing or preparing an act of terrorism, but it is a defence to show that there was a reasonable excuse for the collection or possession of that information. Section 58 (punishable by up to 10 years imprisonment) is a lesser offence than section 57 (now punishable by up to 15 years imprisonment). The collection and recording of relevant information is likely to be a precursor to a more serious wrong and the criminal law targets the lesser wrong in order to deter the greater. 
40.	As for reasonable excuse, it is the fact that information is likely to provide assistance to a person committing or preparing an act of terrorism that imposes on a person in possession the obligation of providing a reasonable excuse for the possession of it. The concept of reasonable excuse had been considered in cases arising out of terrorist legislation in Northern Ireland which was the precursor of the modern legislation under consideration in these proceedings, cases such as R v. McLaughlin [1993] NI 28. There Sir Brian Hutton LCJ sitting in the Northern Ireland court of appeal quashed convictions based on the recording of police messages on the ground that the defendant had there proved that he had the “reasonable excuse” of acting as a radio buff for his own pleasure and interest and not for terrorist purposes (at 35a/b). In R v. Boutrab [2005] NICC 36, Weatherup J in the crown court at Belfast, hearing a case under section 58 of the 2000 Act directed himself (at para 84) that mere curiosity “being an innocent purpose” is capable of being a reasonable excuse for the purposes of section 58(3). Mr Perry submits that in no case prior to K has it ever been suggested that an illicit or normatively improper purpose (albeit other than terrorism) could provide a reasonable excuse. The rationale of K in this connection undermines the normative content of the defence and also fails to take account of the fact that terrorists make use of people who commit crimes for non-political motives (see Report of the Commission to Consider Legal Procedures to Deal with Terrorist Activities in Northern Ireland (Cmd 5185 (1972), the Diplock Report)). The possession of information for a general criminal purpose should not be a reasonable excuse: it is likely to provide practical assistance to a person committing or preparing an act of terrorism; it is not reasonable in itself; and the possession of information likely to be of use to a terrorist does not offend against the principle of legal certainty, since the possessor is likely to be aware of the objective nature and utility of the material in question and therefore can be required to have a good reason for his conduct. The defence of reasonable excuse only arises once the accused has been proved to have been in possession of such material as to give rise to the need for a defence. Once that need arises, an unreasonable let alone an illicit purpose will not provide a defence.    
41.	Mr Perry’s written submissions did not deal with the causation point. He confined himself to the argument that K was wrong to say that possession for a non-terrorist purpose was a reasonable excuse. That was not binding because the passages in question were not part of the ratio of the case; and in any event the decision was per incuriam since the court was not referred to cases where the reasonable excuse defence had been considered, but applied less restrictively. Simpson and Rowe themselves showed that a decision could be reconsidered in such circumstances.
Discussion and decision
42.	These submissions have not persuaded us that we can treat K as other than binding us for relevant purposes. That the material parts of K relevant to this appeal are not merely obiter dicta is clear from the first sentence of its para 16, where Lord Phillips says:
“If section 58 is interpreted in accordance with this judgment, its effect will not be so uncertain as to offend against the doctrine of legality.” 

That shows that all the reasoning which has gone before is directly relevant to the issue in that appeal, which was whether section 58 was too uncertain. 
43.	The question therefore arises whether K was decided per incuriam. It is true that Lord Phillips states that the court in that case received less assistance than it would have liked. Nevertheless, Lord Phillips was familiar with sections 57 and 58, having considered them in Rowe, and indeed Rowe is referred to by him at para 14 of the court’s judgment. That and other authority such as M was also referred to in Zafar which was heard at the same time as K and where judgment was handed down on the same day as in K. Although it seems that the court in K was not assisted by reference to earlier cases on “reasonable excuse”, such cases (a) do not say in terms that only a legitimate and normatively benign motivation can amount to reasonable excuse, and (b) demonstrate that what can amount to a reasonable excuse can depend on the construction of individual statutes: see, for instance, R v. Tabnak [2007] EWCA Crim 380, [2007] 2 Cr App R 4, another recent judgment of this court given by Lord Phillips, on that occasion concerned with the meaning of reasonable excuse under section 35(3) of the Asylum and Immigration (Treatment of Claimants) Act 2004.   
44.	Therefore we regard ourselves as bound by K, in which case Mr Perry recognises that this appeal must succeed.
45.	Having said that, we are not necessarily persuaded that in K this court was saying that questions of purpose, motivation or intention entered into the definition of the offence (as in section 57) as distinct from entering into consideration of the defence of reasonable excuse. However, that does not affect the reasons for which it is necessary in our judgment to allow this appeal. 
The causation point
46.	In those circumstances, it is not necessary to decide whether the judge was right or wrong in his decision on the causation point, and indeed we have read and heard little argument about it. Nevertheless, the point was raised by the appeal and was kept alive by Mr Leist for G. Thus the single ground of appeal conflated both points in saying that –

“The Learned Judge erred in ruling that the Defendant had no defence in law and/or that he had failed to establish an evidential basis to his defence that he had a reasonable excuse under s 58(3) Terrorism Act 2000, in that he was mentally ill at the time of the commission of the offence, namely collecting material of a kind likely to be useful to a person committing or preparing an act of terrorism.” 

Moreover, while devoting his two skeleton arguments since the ruling below almost exclusively to K, Mr Leist did submit, in the final paragraph of his last skeleton, as follows:
“In the event that R v. K does not apply, the appeal should nonetheless be allowed since [G’s] defence may still be considered a reasonable excuse since “winding up” prison officers falls short of “general criminal activity”, and the features of his defence, including his personal health and characteristics as set out in paras 8 and 9 of the supplementary skeleton [ie the first skeleton on appeal], are issues capable of determination by a jury.” 
47.	In the absence of full, or indeed any real, argument on the causation point, we are reluctant to say more than this. Mr Perry acknowledged that, if K was binding, the medical evidence was not necessary to G’s defence of reasonable excuse, but was relevant to it, as it was to count 1 of the indictment. He also very fairly acknowledged that, even if K was not binding or was hereafter overruled, the causation point was a separate issue in the light of which the question of reasonable excuse may well have been raised sufficiently for the purposes of section 118 to come into effect. This was, as we understood it, because he was prepared to recognise that the issue of causation was not concluded by the fact that G’s mental illness did not amount to insanity or compulsion. We would content ourselves with saying that we would ourselves be inclined to agree with that way of looking at things: see R v. Wang [2005] UKHL 9, [2005] 1 WLR 661, [2005] 2 Cr App R 136. Moreover, Tabnak, to which the judge referred for the distinction between ability and inability to make a choice, seems to us to depend on the peculiar factors relating to the different and rather special statute in that case, rather than to express a general principle in relation to causation and reasonable excuse. However, in the absence of detailed argument, we stress that we are not making any decision on that point. 
Conclusion
48.	In sum, we allow this appeal. G’s defence is capable of amounting to reasonable excuse for the purposes of section 58(3) and section 118 of the 2000 Act. It will be a matter for the jury to say whether it does.