Case No: C1/2002/2397
Neutral Citation No: [2003] EWCA Civ 842 
IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM THE HIGH COURT OF 
JUSTICE QUEEN’S BENCH DIVISION 
ADMINISTRATIVE COURT
THE HON MR JUSTICE NEWMAN
Royal Courts of Justice
Strand, 
London, WC2A 2LL

Wednesday 25 June 2003

Before :

LORD JUSTICE AULD
LORD JUSTICE CLARKE
and 
LORD JUSTICE JONATHAN PARKER

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Between :

	THE CONFEDERATION OF PASSENGER TRANSPORT UK	Appellant	
	- and -		
	(1) THE HUMBER BRIDGE BOARD and 
(2)THE SECRETARY OF STATE FOR TRANSPORT LOCAL GOVERNMENT AND THE REGIONS 	Respondent	

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(Transcript of the Handed Down Judgment of
Smith Bernal Wordwave Limited, 190 Fleet Street
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Ms Elisabeth Laing (instructed by Pellys)  for the Appellant
Ms Frances Patterson QC (instructed by Kingston Upon Hull City Council) for the First Respondent.  The Second Respondent was not represented.

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Judgment
As Approved by the Court

Crown Copyright ©

Lord Justice Clarke :

Introduction
1.	This an appeal from an order made by Newman J on 1 November 2002 refusing an application by the appellant for judicial review of a decision of the second respondent with costs.  The judge refused permission to appeal but permission was subsequently granted by Kay LJ.  
The Parties
2.	The appellant is the Confederation of Passenger Transport UK (“the Confederation”) which is an organisation representing the majority, but not all, of the operators of public service vehicles (“PSVs”) in the UK.  The first respondent is the Humber Bridge Board (“the Board”), which is a statutory body having the power to administer the Humber Bridge.  The Board’s powers are contained in two Acts, namely the Humber Bridge Act 1959 and the Humber Bridge Act 1971 (“the 1959 Act” and “the 1971 Act” respectively).  The bridge opened to traffic on 24 June 1981.  The second respondent is the Secretary of State for Transport Local Government and the Regions, who has played no part in these proceedings.    
The Issues
3.	The issues are whether the Board was authorised to levy tolls on large buses under any or all of three Tolls Revision Orders made in 1997, 2000 and 2002 which were made by the relevant Minister, now the Secretary of State for Transport Local Government and the Regions (“the Secretary of State”).  The judge held that the Board was so authorised.  
4.	The question arising under the orders of 1997 and 2000 is the same.  In each case the judge held that the draftsman omitted a reference to large buses by mistake but that it is permissible to construe each order by appropriately reading in the words “large bus”.  The question is whether the court is entitled so to construe the orders.  The question in the case of the 2002 Order is somewhat different.  Here the judge held that a reference to large buses had been deliberately omitted but that they were included within the definition of goods vehicles.  The question is whether, on the true construction of the order, the Board is entitled to levy tolls on large buses and, if so, on what basis.  
The Legislative Framework
5.	Section 61 of the 1959 Act provides as follows:
“(1)	From and after the opening of the bridge for public traffic the Board may demand take and recover in respect of all traffic passing over or on the bridge tolls not exceeding those specified in an order (in this section referred to as ‘the order’) made by the Board and confirmed by the Minister in accordance with the provisions of this section and for any other services rendered by the Board in connection with the bridge such reasonable charges as they may think fit:
Provided that:
(a)	the Board may by resolution if and when they think fit –
(i)	cease to demand take or recover tolls in respect of traffic or certain classes of traffic passing over or on the bridge; and
(ii)	resume demanding taking and recovering such tolls;
(b)	the Board may also (if and when they think fit) allow traffic to use the bridge without paying tolls during such hours or on such occasions as they may from time to time determine.
(2)	The Order when made by the Board shall be submitted to the Minister for confirmation and shall be confirmed by the Minister with or without modification not more than twelve months before the expected opening of the bridge for public traffic.
(3)	After submitting the Order to the Minister for confirmation the Board shall furnish the Minister with such information and particulars certified in such manner as the Minister may require and shall publish in the London Gazette and in such newspapers as the Minister may require a notice stating –
(a)	the general effect of the order; and
(b)	that within a period of forty-two days from the date of the first publication of the notice any person having a substantial interest may object to the Order by giving notice to the Minister accompanied by the grounds of his objection and sending a copy thereof to the Board.
(4)	Before confirming the Order the Minister shall if required by the Board or by any person who has objected to the Order and has not withdrawn his objection and in any other case if he thinks fit cause a local inquiry to be held by such person as he may appoint for the purpose.
(5)	In confirming the Order with or without modification the Minister shall have regard to the financial position and future prospects of the undertaking and the order shall prescribe such maximum tolls as in the Minister’s opinion shall not exceed by more than is reasonable the tolls estimated to be required to be demanded taken and recovered when the bridge is first opened for public traffic to produce an annual revenue not substantially less nor substantially more than adequate to meet such expenditure as is authorised for the several purposes mentioned in section 75 (Application of revenue) of this Act
(6)	The power of the Minister to confirm the Order shall be exercisable by statutory instrument.”
6.	Section 63 provides for a list of the tolls to be appropriately exhibited.  Section 64 provides for the recovery of tolls as a civil debt and section 65 provides that the Board may in some circumstances refuse to permit the use of the bridge by those who knowingly and wilfully refuse or neglect to pay the tolls.  Section 68 provides for certain exemptions from the tolls.
7.	The judge summarised the position under the 1959 Act in this way in paragraphs 5 and 6 of his judgment:
“5.	The following particular points can be made in connection with the above sections and the power of the Board to levy a toll.  The power conferred is an originating power which gives rise to a duty on the Minister to consider confirmation or modification of the Order made by the Board.  The power to levy is contingent upon confirmation being given by the Minister.  The power is expressed in terms which contemplate the Board recovering a toll ‘in respect of all traffic passing over or on the bridge’.  The Act can be taken to contemplate that, where revenue is required for the purposes set out in section 75 (application of revenue), all traffic will be charged where it is reasonable to do so or a specific power is exercised not to do so, or the traffic is exempt.  The Act envisages that there will be classes of traffic specified in the Order.  Thus the proviso at section 61(1)(a)(i) contemplates that where the Board has the power to demand a toll, the toll having been confirmed by the Minister, the Board may by resolution cease to demand and recover the toll which may be in respect of “traffic”, or certain classes of traffic passing over or on the bridge.  Section 75 of the Act imposes an obligation on the Board to apply its revenue in the manner therein specified, laying down the Order of priority for its application.  Priorities 1 to 8 comprise the working and establishment expenses and costs of the undertaking, interest on borrowed money and so forth.  Ninthly, the section provides:
‘Ninthly, in a reduction of tolls which may be demanded taken and recovered under this Act or for such other purpose as may be approved by the Minister’
6.	It follows that for the exercise of the power to levy tolls, both by the Board and the Minister, to be lawful, it must be exercised reasonably and for the purposes specified in the Act.  Subject to the power by resolution to cease to demand to take a toll which can be lawfully demanded, and subject to the exemptions from tolls which are set out in Section 68, the 1959 Act contemplates that the purpose in levying tolls is to raise the revenue necessary for the purposes of the undertaking and in a manner which the Minister regards as reasonable.”
8.	Section 10 of the 1971 Act provides, so far as relevant:
“(1)	If at any time –
(a)	it is represented in writing to the Secretary of State –
(i)	by any person or body representative of persons appearing to the Secretary of State to have a substantial interest in the use of the bridge; or
(ii)	by the Board; or
(b)	it appears to the Secretary of State after consultation with the Board to be expedient;
that in the circumstances then existing or in prospect (including the opening to public traffic of the bridge) all or any of the tolls authorised in pursuance of the Humber Bridge Acts or any classification of vehicles specified in any order for the time being in force under those Acts should be revised, the Secretary of State, may, if he thinks fit make an order revising all or any of such tolls or any classification of vehicles as aforesaid and may fix the date as from which such Order shall be observed until the same expires or is revoked or modified by a further Order of the Secretary of State made in pursuance of this section:
Provided that the Secretary of State shall not make an Order pursuant to paragraph (b) of this subsection at any time except when the Board have borrowed money from the Secretary of State under section 5 (Borrowing from Secretary of State) of this Act and have not repaid the whole of the money so borrowed.
(2)	As soon as may be after the receipt by the Secretary of State of a representation pursuant to subsection (1) of this section from any person or any body other than the Board the Secretary of State shall send a copy of the representation to the Board.
(3)	Before making an Order under this Section the Secretary of State shall if required by-
(a)	any such person or body as is referred to in sub-paragraph (i) of paragraph (a) of subsection (1) of this section, being a person or body who either has made a representation to the Secretary of State pursuant to that subsection or has pursuant to section 11 (Further provisions as to revision of tolls) of this Act objected to the representation made to, or the proposals of, the Secretary of State and has not withdrawn the objection, or
(b)	the Board;
and may in any other case, if he thinks fit, cause a local inquiry to be held by such person as he may appoint for the purpose.
(4)	In the exercise of the powers conferred upon him by this section, the Secretary of State shall have regard to the financial position and future prospects of the undertaking and any Order made by him under this section shall prescribe such tolls as in the opinion of the Secretary of State are reasonably required to be demanded, taken and recovered so as to produce an annual revenue not substantially less, nor substantially more, than is adequate to meet such expenditure as is authorised for the purposes mentioned in section 75 (Application of revenue) of the Act of 1959, as amended by this Act.”
9.	Section 11 (4) provides:
“(4)	The power of the Secretary of State to make an Order under the said section 10 shall be exercisable by statutory instrument and the Secretary of State may by any Order made by him under the said section 10 amend, vary or revoke any of the provisions of any Order made by him under section 61 (Tolls) of the Act of 1959 or under the said section 10.”
The 1979/80 and 1989 Orders
10.	No Tolls Order was made by the Board until 1979.  As the judge observed, no order was necessary since the bridge was not open for traffic until June 1981.  Only one order was made under the 1959 Act.  It was entitled The Humber Bridge Tolls Order 1979 Confirmation Instrument 1980 (SI 1980 No 1137).  It provided, so far as relevant:
“1.	The Humber Bridge Tolls Order 1979, which is an order made by the Humber Bridge Board in exercise of their powers under the said Section 61, prescribing the tolls which the Humber Bridge Board may, from and after the opening of the Humber Bridge for public traffic, demand, take and recover in respect of traffic passing over or on the bridge is confirmed subject to modifications.
2.	The said Order (so modified) is set out in the Schedule hereto.”
11.	The schedule provided as follows:
“1.	This Order may be cited as the Humber Bridge Tolls Order 1979.
2.	The tolls which the Humber Bridge Board may, from and after the opening of the Humber Bridge for public traffic, demand, take and recover in respect of traffic passing over or on the bridge shall be tolls not exceeding those specified in column 2 of the Schedule to this Order in relation to the particular classes of traffic specified in column 1 of that Schedule.”
Column 1 set out what it called classes of traffic and column 2 set out the maximum tolls.  Column 1 included pedestrians and pedal cycles, each of which had a maximum toll of nil.  There followed cars and the like, with appropriate maximum tolls, and the schedule continued: 
“(1)
Class of Traffic	(2) 
Maximum Toll	
Heavy commercial vehicles
        (over 3 tons):
        Class A (2 axle)
        Class B (3 axle)
        Class C (4 or more axles)

Mini-buses with a seating capacity of more than 8 but not more than 16 passengers

Buses and coaches with a seating capacity of 17 and over

£5.20
£6.60
£8.00

£2.90

£5.20”	

12.	It can thus be seen that, so far as buses were concerned, there were express references, first to “mini-buses” with a seating capacity of more than 8 but not more than 16 passengers and secondly to buses and coaches with a seating capacity of 17 and over.  There was, however, no separate definition section in the 1979 Order.  
13.	The next statutory instrument was SI 1989 No 1353 which was entitled The Humber Bridge (Revision of Tolls and Vehicle Classification) Order 1989.  Like all subsequent orders, it was made directly by the Secretary of State under section 10 of the 1971 Act.  The order revoked previous orders and provided, so far as relevant:
“2.	From and after the coming into force of this Order
(i)	for the purpose of the tolls authorised in pursuance of the Humber Bridge Acts 1959 and 1971, vehicles shall be classified in accordance with the classes specified in items 1 to 6 and 8 in column (1) of the scale of charges set out in the Schedule to this Order; and
(ii)	the tolls which the Humber Bridge Board may demand, take and recover in respect of traffic passing over or on the bridge shall be tolls not exceeding those specified in column (2) of the scale of charges set out in that Schedule respectively in relation to each class of traffic specified in column (1) of that scale.”
14.	Paragraph 1 the schedule provided, so far as relevant, as follows
“In this Schedule:
“bus”, “small bus” and “large bus” have the same meanings as in section 19 of the Transport Act 1985.”
In that section “bus” was defined as meaning “a vehicle which is adapted to carry more than 8 passengers”, “large bus” was defined as meaning “a vehicle which is adapted to carry more than 16 passengers” and “small bus” was defined as meaning “a vehicle which is adapted to carry more than 8 but not more than 16 passengers”.  Paragraph 1 of the schedule defined “goods vehicle” as meaning “a mechanically propelled vehicle constructed or adapted for use for the carriage of goods or burden of any description”.
15.	Paragraph 2 of the schedule provided for the maximum scale of charges as follows:
“(1)
Class of Traffic	(2)
Maximum Toll	
1.   Motor cycle with or without 
      sidecar                                   

2.   Car
       Goods vehicle having a
       maximum weight exceeding 3.5  
       tonnes

3.   Goods vehicle having a maximum 
       weight exceeding 3.5 tonnes but  
       not exceeding 7.5 tonnes
       Vehicle within class 2 above with
       trailer
       Small bus
       Motor caravan              

4.   Goods vehicle having a maximum 
      weight exceeding 7.5 tonnes with  
      2 axles
      Large bus

5.   Goods vehicle having a maximum 
      weight exceeding 7.5 tonnes with
      3 axles

6.   Goods vehicle having a maximum  
      weight exceeding 7.5 tonnes with   
      4 or more axles

7.   Pedestrian

8.   Pedal cycle	      70p

£1.60

£2.90

£6.50

£8.70

£10.90

                            Nil

  Nil”

16.	The position was thus quite clear under the 1979/80 and 1989 Orders.  Large buses were expressly included and with maximum tolls of £5.20 and £6.50 respectively.
The 1997 Order
17.	The next order was 1997 SI No 1950 and was entitled The Humber Bridge (Revision of Tolls Vehicle Classification) Order 1997.  The order was made on 6 August 1997 and expressed to come into force on 7 August 1997.  It revoked the 1989 Order.  By paragraph 2 it provided:
“From and after the coming into force of this Order for the purposes of the tolls authorised in pursuance of the Humber Bridge Acts 1959 and 1971, the tolls which the Humber Bridge Board may demand, take and recover in respect of traffic passing over or on the bridge shall be tolls not exceeding those specified in column (2) of the scale of charges set out in the Schedule to this Order with respect to each class of traffic specified in column (1) of that scale.”
The definitions were the same as in the 1989 Order and, as in that order, the schedule provided that “in this Schedule “bus”, “small bus” and “large bus” have the same meanings as in section 19 of the Transport Act 1985”.  Unfortunately, although there was a reference in the operative part of the order to “small bus” there was no reference to “bus” or, more importantly for present purposes, to “large bus”.
18.	Paragraph 2 of the schedule provided:
“The scale of charges referred to in article 2 of this Order shall be as follows:
         (1)
Class of Traffic	        (2)
Maximum Toll	
1.  Motor cycle with or  without sidecar

2.   Car 
      Goods Vehicle having a maximum 
       weight not exceeding 3.5 tonnes

       
3.   Goods Vehicle having a maximum
      weight exceeding 3.5 tonnes but
       not exceeding 7.5 tonnes
       Vehicle in class 2 above with
       Trailer
       Small bus (up to 16 passengers
       excluding driver)
       Motor Caravan

4.   Goods Vehicle exceeding 7.5 tonnes
      maximum weight with 2 axles

5.   Goods Vehicle exceeding 7.5 tonnes
      maximum weight with 3 axles

6.   Goods Vehicle exceeding 7.5 tonnes
      maximum weight with 4 or more
      axles” 
	       £1.00

                     £2.30 

                     £4.10

                      £9.20

                    £12.30

                    £15.40	

19.	There can, to my mind, be no doubt that the draftsman omitted a reference to “large bus” by mistake, not only because of the reference to “large bus” in the definition but also because of its historical context (to which I return below) and because the Explanatory Note states that one of the “changes now made” is “(c) the toll for good (sic) vehicles over 7.5 tonnes maximum weight with 2 axles and buses and coaches with 17 or more seats is increased from £6.50 to £9.20.”  To my mind that makes it clear beyond a peradventure that the draftsman omitted a reference to large buses by mistake and that, had he not made a mistake, he would have included them in class 4 with a new maximum toll of £9.20.
20.	I shall return below to the question what materials it is permissible to have regard to in deciding whether a mistake was made and, if a mistake was made, what it was, but it is convenient to refer here to the historical context of the 1997 Order.  
21.	In accordance with the provisions of the 1959 and 1971 Acts public enquiries were held before the 1980, 1989 and 1997 Orders, as indeed one was held prior to the 2002 Order.  The report of the inspector who held the first enquiry in 1980, Mr Holden, included the following in paragraph 252 of his report:
“The Order proposes that buses and coaches of whatever size, other than mini-buses, should pay the same toll as goods vehicles over 3 tonnes with 2 axles.  If tolls are to be charged, I see no reason why they should not be levied on all vehicles.  In my view the toll on a bus is as much part of the operator’s running costs as his licence fee or his fuel.  Whether the toll should be passed on to the passengers using the service affected or treated as part of the operator’s overall costs is a matter for him.”
22.	The inspector recommended the order made by the Board to the Secretary of State, subject only to drafting changes which the Secretary of State adopted.  Paragraph 180 of the inspector’s report included this:
“To remove any doubt about the meaning of the various categories of vehicle mentioned in the Order, the Board asked that the descriptions in the Order be modified as follows:
…
(e)	after mini-buses add “with seating capacity of 7 to 16 passengers inclusive”;
(f)	after buses and coaches add “with a seating capacity of 17 and over”.”
23.	The inspector’s report after the inquiry before the 1989 Order included the following in paragraph 91:
“The opportunity has now been taken to seek to amend vehicle classifications in the proposed new tolls Order in order to make the terminology consistent with vehicles descriptions currently found in other legislation.”
24.	In 1996 the inspector conducting the inquiry prior to the 1997 Order received a representation for the creation of a new class of bus, called a “midi-bus”, which could be established for the 17 to 35 seat vehicle and for a toll to be charged somewhere between classes 3, the mini-bus, and 4, the large bus.  The inspector concluded:
“I am not persuaded that there is any justification for creating a new class of midi-bus, between class 3 and 4.  In all classes there will be vehicles on the borderline and a claim could be made for a reduced rate for them.  The present classes fit national legislation and there is certainty and practicality in retaining the recognised classes.  I had no breakdown of the number of vehicle journeys that would fall into the midi-bus category and I have to have regard to the over-riding need to increase income.”
25.	The Secretary of State accepted the inspector’s report in a decision letter dated 6 August 1997, the very day on which the 1997 Order was made.  Paragraph 2 of the letter included the following:
“The tolls charged and proposed to be charged at the Bridge are as follows:
Category of Vehicle			     Present Toll       Proposed Toll 
		Class	    Vehicle				  £		   £
	   4
       	Goods Vehicle exceeding 7.5 tonnes maximum weight with 2 axles
Large bus (17 or more passengers including driver) “	    6.50	      9.20	

26.	As the judge observed, “it will be obvious that, despite the expressed intention of the Secretary of State to implement the Inspector’s recommendations, which included “large bus” within class 4, the 1997 Order did not do so”.  The decision letter is to my mind further powerful evidence, if any such evidence were needed, that an express reference to ‘large bus’ was omitted from the 1997 Order by mistake.  
Discussion re 1997 Order
27.	It is common ground before us, as it was before the judge, that the Board cannot change tolls in respect of large buses, or indeed anything else, unless there is clear and distinct statutory authority to do so: see eg McCarthy & Stone (Developments) Ltd v Richmond upon Thames LBC [1992] 2 AC 48 per Lord Lowry at 67-8, applying Attorney-General v Wilts United Dairies Limited (1921 37 TLR 884 (CA) and (1922) 38 TLR 781 (HL), especially per Scrutton LJ at p 885.
28.	The question is whether there is such authority in the 1997 Order.  If the words of the order are given their ordinary and natural meaning there is on the face of it no such authority because there is no reference to “large bus” in the operative part of the order despite the reference to “large bus” in the definition section of it.
29.	Ms Patterson submits on behalf of the Board that even if it were held that “large bus” was omitted and cannot be read into the order, the order can be read as prescribing maximum tolls for those classes of traffic which it identifies and that vehicles in unidentified classes can be charged at the maximum rate specified for the nearest equivalent class, which in the case of large buses was that of goods vehicles over 7.5 tonnes maximum weight with 2 axles.  She says that this is what in fact happens in the case of, say, combine harvesters, which are not mentioned in the order.
30.	I am bound to say that, for my part, I have difficulty in accepting that submission.  There is nothing in the 1997 Order (and there had been nothing in the two earlier orders) which suggests that it was open to the Board to charge vehicles of a class not mentioned in the order at the nearest equivalent rate.  In my opinion, if the Board wishes to charge tolls on that basis it should ask the Secretary of State to make an order which so provides.  However, that was not the basis on which the judge decided the case.  I therefore return to his reasoning.
31.	The judge accepted Ms Patterson’s submission on behalf of the Board that in paragraph 2 of the schedule the words “large bus” should be treated as being added to or read into class 4 under the reference to “Goods vehicle exceeding 7.5 tonnes maximum weight with 2 axles”.  
32.	He applied the principles stated in two House of Lords cases.  The first is Jones v Wrotham Park Estates [1980] AC 74, where Lord Diplock said at p 105:
“My Lords, I am not reluctant to adopt a purposive construction where to apply the literal meaning of the legislative language would lead to results which would clearly defeat the purpose of the Act.  In doing so the task on which a court of justice is engaged remains one of construction; even where this involves reading into the Act words which are not expressly included in it.  Kammins Ballroom Co Ltd v Zenith Investments (Torquay) Ltd [1971] AC 850 provides an instance of this; but in that case the three conditions that must be fulfilled in order to justify this course were satisfied.  First, it was possible to determine from a consideration of the provisions of the Act read as a whole precisely what the mischief was and it was the purpose of the Act to remedy; secondly, it was apparent that the draftsman and Parliament by inadvertence overlooked, and so omitted to deal with, an eventuality that required to be dealt with if the purpose of the Act was to be achieved; and thirdly, it was possible to state with certainty what were the additional words that would have been inserted by the draftsman and approved by Parliament had their attention been drawn to the omission before the Bill passed into law.  Unless this third condition is fulfilled any attempt by a court of justice to repair the omission in the Act cannot be justified as an exercise of its jurisdiction to determine what is the meaning of a written law which Parliament has passed.  Such an attempt crosses the boundary between construction and legislation.  It becomes a usurpation of a function which under the constitution of this country is vested in the legislature to the exclusion of the courts.”
33.	The second case, which is of particular significance for present purposes, is Inco Europe Limited v First Choice Distribution [2000] 1 WLR 586, where Lord Nicholls, with whom the other members of the House agreed, set out the relevant principles.  He did so in the context of a case in which the House of Lords had to decide whether an appeal lay to the Court of Appeal from a decision made at first instance under section 9 of the Arbitration Act 1996.  Section 18 of the Supreme Court Act 1981 as amended by section 107 and paragraph 37(2) of schedule 3 to the 1996 Act provided a relevant saving but, on its literal construction, the saving did not apply and section 9 itself was silent on the point.  Lord Nicholls pointed out that read literally the provisions gave rise to an argument which was unanswerable, but (as the judge observed) he concluded that it was clear beyond a peradventure that “Homer, in the person of the draftsman of schedule 3 to the Act of 1996, nodded”.
34.	Lord Nicholls examined the legislation and the history of the legislation and expressed the relevant principles in this way at pp 592C-593A:
“I freely acknowledge that this interpretation of section 18(1)(g) involves reading words into the paragraph.  It has long been established that the role of the courts in construing legislation is not confined to resolving ambiguities in statutory language.  The court must be able to correct obvious drafting errors.  In suitable cases, in discharging its interpretative function the court will add words, or omit words or substitute words.  Some notable instances are given in Professor Sir Rupert Cross’s admirable opuscule, Statutory Interpretation, 3rd ed (1995), pp 93-105.  He comments, at p 103:
“In omitting or inserting words the judge is not really engaged in a hypothetical reconstruction of the intention of the drafter or the legislature, but is simply making as much sense as he can of the text of the statutory provision read in its appropriate context and within the limits of the judicial role.”
This power is confined to plain cases of drafting mistakes.  The courts are ever mindful that their constitutional role in this field is interpretative.  They must abstain from any course which might have the appearance of judicial legislation.  A statute is expressed in language approved and enacted by the legislature.  So the courts exercise considerable caution before adding or omitting or substituting words.  Before interpreting a statute in this way the court must be abundantly sure of three matters: (1) the intended purpose of the statute or provision in question; (2) that by inadvertence the draftsman and Parliament failed to give effect to that purpose in the provision in question; and (3) the substance of the provision Parliament would have made, although not necessarily the precise words Parliament would have used, had the error in the bill been noticed.  The third of these conditions is of crucial importance.  Otherwise any attempt to determine the meaning of the enactment would cross the boundary between construction and legislation: see per Lord Diplock in Jones v Wrotham Park Settled Estates [1980] AC 74, 105-106.  In the present case these three conditions are fulfilled.”
35.	The judge quoted those paragraphs from the speech of Lord Nicholls.  However, Ms Laing has drawn our attention to the fact that the judge did not quote the next paragraph of his speech, which she says qualifies what had gone before, as follows:
“Sometimes, even when these conditions are met, the court may find itself inhibited from interpreting the statutory provisions in accordance with what it is satisfied was the underlying intention of Parliament.  The alteration in language may be too far-reaching.  In Western Bank Ltd v Schindler [1977] Ch 1, 18, Scarman LJ observed that the insertion must not be too big, or too much at variance with the language used by the legislature.  Or the subject matter may call for a strict interpretation of the statutory language, as in penal legislation.  None of these considerations apply in the present case.  Here the court is able to give a construction of the statute which accords with the intention of the legislature.”
36.	In my opinion the principles stated by Lord Nicholls in those passages are indeed the relevant principles to apply in this case.  The House of Lords was considering primary legislation but it appears to me that the same or very similar principles must apply to statutory instruments like the 1997 Order.  The judge held that each of the conditions identified by Lord Nicholls was satisfied here.  
37.	He summarised his reasons in paragraph 24 of his judgment as follows:
“It was common ground that two words “large bus” have been omitted from the two Orders because the draftsman had slipped up.  It is clear from the terms of the two Decision Letters that the Minister intended to confirm the Board’s exercise of power and to make large buses liable to pay the toll specified in class 4.  It is obvious from the inclusion of a definition of ‘large bus’ in the Instrument that “large bus” was envisaged as a category or class.  The Explanatory Note is not a legitimate aid to the interpretation of the Instrument, but this being delegated legislation at the hand of the Minister, which is not required to be laid before Parliament, it seems to me that the court commits no impropriety in having regard to the plain intention of the maker of the Instrument, and the content of the Instrument, which confirms the intention but nevertheless by omission, fails to fully implement it.  There being a general power contained in section 61(1) of the 1959 Act, reaffirmed as a continuing power for revisions to take place pursuant to section 10 of the 1971 Act, notwithstanding that the power is an inchoate power until confirmed by the Minister, there can, in my judgment, be no basis for concluding that the court would be stepping outside its constitutional role by rectifying the omissions so as to include large buses as traffic liable to a levy.  Since the omission of ‘large bus’ from class 4 in the two Orders is to be regarded as an omission, there is no rational basis for concluding that there being a power to charge all traffic passing over the bridge, “large bus” should be treated by the court as exempt.  In my judgment the Board’s intention to classify ‘large bus’ as being liable to a toll is sufficiently plain from the general power in section 61(1), the orders drawn by the Board to include it, the respective Decision Letters of the Secretary of State to confirm them as laid before him, and the inclusion in the definition section of the Instruments of “large bus”.  I thus have no doubt as to the first of the three matters referred to by Lord Nicholls, namely the intended purpose of the statute or provision in question.  I have no doubt as to the second, that it arose by inadvertence on the part of the draftsman, and as to the third, there is no difficulty in concluding upon the precise words which would have been used by the draftsman (in effect by the Secretary of State), because he had used them in his Decision Letters, namely ‘large bus’ as being included in class 4 of the classification in the scale of charges in each of those Instruments.”
38.	I entirely agree with those conclusions.  If anything, I would go further and make more use of the explanatory note than the judge did.  However, quite apart from the explanatory note, there are two key considerations which show that a mistake was made.  First, it seems to me that if the 1997 Order is construed in its historical context, which includes the 1979/80 and 1989 Orders, it is inconceivable that either the Board or the Secretary of State intended to exclude large buses from the classes of vehicle expected to pay tolls, especially since the purpose of the tolls was to help to recoup the very substantial costs of building the bridge.  Secondly, the 1997 Order itself shows that it was intended to include large buses because there would otherwise have been no purpose in including a provision which expressly stated that “in this Schedule “bus”, “small bus” and “large bus” shall have the same meanings as in the Transport Act 1985”.  It seems to me to be plain from that provision alone that the draftsman intended to include large bus in one of the classes of traffic identified in the schedule.
39.	Thus it can be seen from the terms of the instrument itself that a mistake was made by or on behalf of the Secretary of State who made it.  The next question is what materials can be used by the courts to identify the nature of the mistake which was made.  Ms Laing submits on behalf of the Confederation that none of the materials deployed by the judge can properly be used.  She says that if this is a hard case so be it, but hard cases make bad law.
40.	Ms Laing submits that the approach adopted by the judge was wrong in principle.  She submits that his approach involves inserting words into the 1997 Order in order to reflect the subjective intention of the draftsman and not his intention ascertained objectively or, as it is sometimes put, the objective intention of the maker of the instrument.  She submits that the general rule is that the court will focus only on material contained in the instrument itself or expressly incorporated within it and that it will only rarely permit reference to be made to extraneous material.  
41.	She gave as one example the court’s approach to planning permission, by reference to Slough Estates v Slough Borough Council (No 2) [1971] AC 958, per Lord Reid at p 962 H.  However, I do not for my part think that any real assistance is to be gained from examples in so different a field.
42.	More importantly for present purposes, Ms Laing relies upon the approach of the House of Lords to the use of extraneous material as an aid to construction as exemplified for example by the decision in R v The Secretary of State for the Environment ex p Spath Holme Limited [2001] 2 AC 349, where there was considerable discussion (and some disagreement) as to the use to be made or Parliamentary materials as an aid to the construction of a statute, albeit in the context of a consolidating statute, which the tolls orders are not.  It is not I think necessary for us to express a view upon such points of disagreement as there were in Spath Holme.    
43.	Ms Laing relies upon the statement of Lord Bingham at p 388 that the overriding aim of the court must always be to give effect to the intention of Parliament “as expressed in the words used”.  He also stressed (at p 391) the principles identified in Lord Browne-Wilkinson’s speech in Pepper v Hart [1993] AC 593, namely that statements made in Parliament were only permissible as an aid to construction where (a) legislation was ambiguous or obscure, or led to an absurdity, (b) the materials consisted of statements by the minister or promoter of the bill together with such other material as might be necessary to understand such statements and their effect and (c) the effect of such statements was clear.
44.	Ms Laing also relies upon a number of statements in the speech of Lord Nicholls in Spath Holme.  Indeed both Ms Laing and Ms Patterson referred in some detail to what Lord Nicholls described as first principles, which are set out from pages 396D to 398E.  I cannot of course set the whole of that passage here but it does seem to me that his approach points the way in the instant case.  He first stressed that the role of the courts is one of interpretation of the relevant statutory provision.  Thus he said at pp 396E to 397A:
“The purpose for which a power is conferred, and hence its ambit, has to be inferred from the language used, read in its statutory context and having regard to any aid to interpretation which assists in the particular case.  In either event, whether the purpose is stated expressly or has to be inferred, the exercise is one of statutory interpretation.
Statutory interpretation is an exercise which requires the court to identify the meaning borne by the words in the particular context.  The task of the court is often said to be to ascertain the intention of Parliament expressed in the language under consideration.  This is correct and may be helpful, so long as it is remembered that the “intention of Parliament” is an objective concept, not subjective.  The phrase is a shorthand reference to the intention which the court reasonably imputes to Parliament in respect of the language used.  It is not the subjective intention of the minister or other persons who promoted the legislation.  Nor is it the subjective intention of the draftsman … .  As Lord Reid said in Black-Clawson International Ltd v Papierwerke Waldhof-Aschaffenburg AG [1975] AC 591, 613: “We often say that we are looking for the intention of Parliament, but that is not quite accurate.  We are seeking the meaning of the words which Parliament used.””
45.	Lord Nicholls then considered various aids to interpretation, first internal aids and then external aids.  As to the latter he said this (at p 397 C):
“Or the aids may be external to the statute, such as its background setting and its legislative history.  This extraneous material includes reports of Royal Commissions and advisory committees, reports of the Law Commission … and a statute’s legislative antecedents.
… Nowadays the courts look at external aids for more than merely identifying the mischief the statute is intended to cure.  In adopting a purposive approach to the interpretation of statutory language, courts seek to identify and give effect to the purpose of the legislation.  To the extent that extraneous material assists in identifying the purpose of the legislation, it is a useful tool.”
46.	In the next passage of his speech Lord Nicholls stressed that that approach is subject to an important caveat because, as Lord Diplock put it in Fothergill v Monarch Airlines Ltd [1981] AC 251, 279 (in a passage relied upon by Ms Laing):
“The source to which Parliament must have intended the citizen to refer is the language of the Act itself.  These are the words which Parliament has itself approved as accurately expressing its intentions.  If the meaning of those words is clear and unambiguous and does not lead to a result which is manifestly absurd or unreasonable, it would be a confidence trick by Parliament and destructive of all legal certainty if the private citizen could not rely upon that meaning but was required to search through all that had happened before and in the course of the legislative process in order to see whether there was anything to be found from which it could be inferred that Parliament’s real intention had not been accurately expressed by the actual words that Parliament had adopted to communicate it to those affected by the legislation.”
47.	Lord Nicholls then considered the possible use of external aids in order to determine whether the words of a statute are clear and ambiguous or indeed in order to displace meanings which are otherwise clear and unambiguous and not productive of absurdity.  It is not, however, to my mind necessary for us to consider such problems in the instant case because it is plain from the language used that a mistake was made by the maker of the 1997 Order and it seems to me that the order is neither clear nor unambiguous on its face because it does not state where in the schedule large buses are to be included.  Moreover, it seems to me that without adding a reference to large buses at an appropriate place, the order is in this respect (as the cases put it) productive of absurdity.
48.	Ms Patterson submits that in these circumstances it is permissible to use the explanatory note, the Secretary of State’s decision letter and indeed the inspector’s report as legitimate extraneous aids to identify the purpose of the 1997 Order and the words omitted.  I agree.  
49.	As to the explanatory note, I recognise that it has been held that an explanatory note is not part of a statutory instrument, but I see no reason why it should not be used to help to resolve the question whether any words were omitted from the statutory instrument by mistake.  In Pickstone v Freemans plc [1989] AC 66 Lord Oliver said at p 127 that, while the explanatory note is not part of the regulations, it is of use in identifying the mischief which the regulations were attempting to remedy.  If that is so, I do not see why it cannot be used to help decide both whether any words were omitted from the draft by mistake and, if so, what those words were.  The sole purpose of the order was to increase the tolls paid by vehicles using the bridge, one class of which was large buses.  The explanatory note shows that one of the purposes of the order was to increase the maximum tolls which the Board could levy on large buses to £9.20.
50.	That approach seems to me to be entirely consistent with the views expressed by Lord Steyn in R (Westminster City Council) v National Asylum Service [2002] UKHL 38 [2003] LGR 23, especially in paragraph 5, although it is right to have in mind that the opinions expressed there were obiter and related to the type of explanatory notes of the kind which, as he put it, now accompany most public bills in their progress towards enactment by Parliament: see paragraphs 3 and 4 of his speech. 
51.	As to the decision letter and the inspector’s report, again they seem to me to be admissible extraneous materials since they provide the immediate context for the 1997 Order and in particular they make clear that one of its statutory purposes was to increase the maximum tolls for large buses to the same as those for goods vehicles exceeding 7.5 tonnes maximum weight with 2 axles, namely to £9.20.
52.	In the somewhat different context of ministerial statements to Parliament, the cases, including Pepper v Hart and Spath Holme, stress that the parliamentary statement relied upon must be clear and unequivocal.  Applying a similar principle here, it seems to me that the explanatory note, whether by itself or taken together with the decision letter and the inspector’s report, makes it clear beyond a peradventure what was intended.           
53.	For all these reasons, I would not accept Ms Laing’s submissions and would hold that the judge was right, essentially for the reasons which he gave.  I would hold that, on its true construction, the 1997 Order should be read as including the words “large bus” in class 4 of column 1 of the schedule to the order.  In particular I agree with the judge that the court can be abundantly sure of the three matters identified by Lord Nicholls in the Inco Europe case, namely (1) the intended purpose of the order, (2) that the draftsman and the Secretary of State failed by inadvertence to give effect to that purpose and (3) the substance of the provision that would have been made but for the mistake.  Moreover none of the considerations adverted to by Lord Nicholls and which are quoted in paragraph 35 above but not referred to by the judge applies here.  It follows that I would dismiss the appeal in so far as it relates to the 1997 Order.
The 2000 Order
54.	SI 2000 No 204, which was made on 8 February 2000 and came into force on 1 April 2000, is entitled The Humber Bridge (Revision) Order 2000 and was in the same terms as the 1997 Order, which it revoked.  The explanatory note was also in the same terms as that attached to the 1997 Order.  The only difference in each case was the figures.  Thus in the body of the order the maximum toll in respect of a class 4 vehicle, namely a “Goods Vehicle exceeding 7.5 tonnes maximum weight with 2 axles” was £9.60 and in the explanatory note it was stated that “the toll for goods vehicles over 7.5 tonnes maximum weight with 2 axles and buses and coaches with 17 or more seats is increased from £9.20 to £9.60”.
55.	The Secretary of State’s decision letter was also dated 8 February 2000 and included the following:
“2.	Although there are no formal objections outstanding the bus operators who withdrew their objections asked the Secretary of State to give careful consideration to their representations about bus tolls.  The Secretary of State has therefore determined your toll application without a public enquiry held but, in doing so, has given careful consideration to the representations of the bus operators.
3.	The tolls charged and proposed for the bridge are as follows:”
There then followed a box containing classes of vehicles which included in class 4 “large bus (17 or more passengers including driver)”.
56.	In these circumstances precisely the same considerations apply to the 2000 Order as apply to the 1997 Order.  It was accepted on all sides that the appeal relating to the 2000 Order should be determined in the same way as the appeal relating to the 1997 Order.  It follows that I would also dismiss the appeal in so far as it relates to the 2000 Order, for substantially the same reasons as in the case of the 1997 Order.
The 2002 Order    
57.	The 2002 Order is not in the same terms as those that preceded it and presents somewhat different problems for the court.  It is entitled the Humber Bridge (Revision of Tolls) Order 2002, was made on 22 March 2002 and came into force on 1 April 2002.  It revoked the 2000 Order.  By paragraph 2 it provides:
“From and after the coming into force of this Order for the purposes of the tolls authorised in pursuance of the Humber Bridge Acts 1959 and 1971, the tolls which the Humber Bridge Board may demand, take and recover in respect of traffic passing over or on the bridge shall be tolls not exceeding those specified in column (2) of the scale of charges set out in the Schedule to this Order with respect to each class of traffic specified in column (1) of that scale.”
58.	Paragraph 1 of the schedule provides, so far as relevant:
“In this Schedule:
“bus” and “small bus” shall have the same meanings as in section 19 of the Transport Act 1985;
…
“goods vehicle” means a mechanically propelled vehicle constructed or adapted for use for the carriage of goods of burden of any description; …
Thus, unlike the schedules in the earlier orders, paragraph 1 of the schedule to the 2002 Order makes no reference to large bus.  
59.	Paragraph 2 of the schedule includes the following:
“The scale of charges referred to in article 2 of this Order shall be as follows:
                 “(1)					                (2)
           Class of Traffic			        Maximum Toll
 2   	Motor Car
Motor Caravan
Goods vehicle having a maximum weight not exceeding 3.5 tonnes
	£2.50	
 3       	Goods vehicles having a maximum weight exceeding 3.5 tonnes but not exceeding 7.5 tonnes
Vehicle in class 2 above with trailer
Small bus (up to 16 passengers excluding driver)
	£4.50	
 4	Goods Vehicle exceeding 7.5 tonnes maximum weight with 2 axles
 	£10.00”	

60.	There were two other classes, namely goods vehicles exceeding 7.5 tonnes maximum weight with 3 and with 4 or more axles with a maximum toll of £13.40 and £16.70 respectively.  The explanatory note explains the increases in each case and includes the following:
“(b) 	The toll for goods vehicles over 3.5 and up to 7.5 tonnes maximum weight and for small buses (up to 16 passengers excluding the driver) is increased from £4.30 to £4.50.
 (c)	The toll for good (sic) vehicles over 7.5 tonnes maximum weight with 2 axles is increased from £9.60 to £10.00”
It contains no reference to large buses.
61.	The judge said this in paragraph 14:
“It is plain from this Order that the draftsman deliberately left out “large bus” from the definition in the Schedule and there is no mention of “large bus” at all.  If a large bus, namely a bus having 17 people or more is to fall within any category or classification under the Order, it must be as a goods vehicle.  It will do so if it can be said to be a mechanically propelled vehicle constructed or adapted for use for the carriage of a ‘burden’ of some description.  According to whether a bus has 2 axles, 3 axles or 4 axles, it will be charged accordingly.”
He then set out his conclusions with regard to the “2002 Order in paragraph 26 of his judgment in these terms:
“The case for the power to levy a toll on large buses according to whether they have 2, 3 or more axles, depends solely upon the definition of “goods vehicle” in the 2002 Order.  The definition has a long history in transport legislation and is thus not specifically devised to embrace buses.  The converse appears to be the case; as a definition of goods vehicle it appears in legislation where buses are specifically categorised.  A driver of goods vehicle requires a Heavy Goods Vehicle (HGV) licence.  A driver of a bus requires a Public Service Vehicle (PSV) licence.  Despite the ease with which the Secretary of State could have covered past error or omission by including “large bus” in each of the categories 4, 5 and 6, as the court has done in connection with the 1997 and 2000 Orders, he did not do so in 2002.  The drafting must be regarded as deliberate, without error.  What one can discern is that, in the light of the earlier drafting, it was intended that the classification of “bus” and “small bus” should have specific relevance to the 2002 Order.  It can be discerned by reason of the amendment to exclude the words “large bus” from the definition section, that it was intended that it should not be regarded as a category on its own.  The simple question which arises, therefore, is whether a bus carrying passengers falls, within the definition of a mechanically propelled vehicle carrying ‘burden of any description’.  Although the definition of goods vehicle which has been employed may have a long established history, it seems to me that the words “burden of any description” must be given the broad meaning which the word ‘any’ itself suggests.  Having regard to the clear purpose behind the Board having the power to levy a toll on all traffic passing over the bridge, where words are used which are according to their ordinary meaning (as opposed to prior statutory use) wide enough to embrace a “large bus” it seems to me effect should be given to the underlying intention and purpose of this legislation.  To describe passengers as “burden of any description” may have an antiquated ring about it, but passengers can be regarded as burden in this context because they create a weight which the vehicle has to carry.  Further, since the class is capable of being defined by the weight of the vehicle and the number of axles, a classification by reference to the number of persons carried or particular “burden” would be otiose.  There is in my judgment no strain to the language used to include “large bus” within the definition of goods vehicle.  I have concluded that the Order as drawn and made includes large buses within each of the categories, class 4, 5 and 6, according to how may axles a bus has.”
62.	It can thus be seen that the judge held that the effect of the order was that the Secretary of State had introduced a new regime for large buses which depended upon their weight and the number of axles.  That was different from the previous approach, which was that large buses should be charged at the same maximum rate as goods vehicles over 7.5 tonnes maximum weight with two axles.  Moreover the maximum toll had throughout been four times the maximum toll for cars. It follows that the effect of the 2002 Order on the judge’s approach is that for large buses with 3 or more axles the maximum toll was significantly increased.  I am bound to say that it seems to me be most unlikely that that was what intended.  
63.	Further, Ms Laing submits that it would be surprising and incongruous if, as the judge held, a large bus is a goods vehicle for the purpose of the 2002 Order but not for the purpose of the earlier orders, which (as she puts it) are in pari materia, or for the purpose of national and EU transport legislation.  That is in my opinion a powerful point.  So too is her submission that it is not natural in this context to include passengers in the expression “burden of any description”.
64.	On the other hand I agree with the judge that, in the light of the earlier drafting, it was intended that the classification of “bus” and “small bus” should have specific relevance in the 2002 Order.  The reference to “bus” as well as “small bus” suggests that the draftsman intended to include a reference to a bus as well as to a small bus, since there would otherwise be no purpose in referring to “bus” at all.  More importantly, (as stated in paragraph 38 above with regard to the earlier orders) it seems to me to be inconceivable that the Secretary of State intended to exclude large buses from the classes of vehicles expected to pay tolls, especially since the purpose of the tolls was to help recoup the very substantial costs of building the bridge.  
65.	In these circumstances, it seems to me that the 2002 Order as drafted makes no real sense.  It makes no sense to conclude, as Ms Laing submits, that the Secretary of State intended to exclude large buses altogether.  Equally it makes no sense to conclude that the Secretary of State intended to treat large buses (but not small buses) as “goods vehicles” within the meaning of paragraph 1 of the schedule to the Order or, for the first time, to charge by reference to number of axles.  In these circumstances, I would hold that, as drafted, the 2002 Order is ambiguous or obscure and, indeed productive of absurdity.
66.	In these circumstances, it seems to me to be permissible to have regard to the extraneous materials to which I referred earlier in order determine what was objectively intended by the maker of the instrument.  I recognise that this is in some respects less straightforward than in the case of the 1997 and 2000 Orders because the explanatory note does not help to identify where large buses should be included.  Indeed, on its own it might suggest that large buses were excluded.  However, the other materials seem to me to point the way.
67.	The sequence of events which led to the 2002 Order was similar to the events which led to the earlier orders.  So far as I can see, it was broadly as follows.  The Board prepared a detailed case for further increases and submitted it to the Secretary of State.  In a letter dated 1 March 2001 it sought increases in each of the various classes and, although we have not seen a copy of that letter, the Board’s position can be seen from the report of the inspector, Mr Tipping, who held an inquiry on 19 December 2001.         
68.	His report was dated 30 January 2002.  The section of it which set out the Board’s case, included the following:
“3.5	The increases now proposed would take effect, if confirmed, on 1 April 2002, and apply during the period to 31 March 2004.  The 2000 Order retained eight classes of Bridge user and these would remain unchanged.  Of these, two classes, pedestrians and cyclists, would continue to use the Bridge free of charge.  The toll chargeable to motorists would increase by 10 pence to £1.10, representing the smallest convenient increase compatible with current coinage.  The tolls chargeable to the remaining five classes would increase, with some limited rounding, by 4%, representing the Board’s best estimate of inflationary trends during the period 1 April 2002 to 31 March 2004.  This estimate had been formulated combining experience of past inflation with Government estimates of future inflation.
 3.6	Thus the toll chargeable to motor cars would increase by 10 pence or 4.16% to £2.50.  Since 1989, the tolls chargeable to heavier vehicular traffic had been based on weight and number of axles, irrespective of type of vehicle.  Coaches and large buses (those carrying more than 16 passengers excluding the driver) were thereby included in class 4: “Goods Vehicle exceeding 7.5 tonnes maximum weight with 2 axles”.  The Board’s current proposal was to increase the toll currently chargeable to such vehicles, £9.60, by 40 pence to £10.-00, an increase of 4.16%.”
It is thus clear that the Board was seeking an increase to £10.00 for large buses on the basis that they would be included in class 4, not on the basis that they might be included in a higher class according to the number of axles.  
69.	In the section of his report dealing with the case for the objectors, the inspector set out the case for the PSV operators.  It included the following:
“4.2	The very high existing Bridge tolls imposed on PSVs, that is, on large buses and coaches, using the Bridge were unacceptable and were causing operators to reduce crossings.  The proposed toll increases would accelerate this trend.    Reducing the toll would encourage an increase in Bridge crossings by PSVs and increase toll revenue from that source.
 4.3	The tolls charged for use of the Bridge were the highest for any estuarial crossing in Britain. …  Moreover, the toll charged for a coach or large bus was four times that charged to a motor car, again the highest differential imposed on any British estuarial crossing.  This fourfold differential had been applied since the inception of the Bridge, but had always been onerous and unfair.  If the board’s toll proposal were implemented, the cash difference between the undiscounted tolls for a single crossing by a car (£2.50) and a large bus (£10.00) would rise to £7.50.  The average car:large bus ratio for all other UK crossings was 1:1.87.”
It is thus plain that the PSV operators concerned understood the Board’s proposals.  They correctly appreciated that the proposal was to charge large buses at four times the rate for cars, as had been done since the inception of the bridge, and to charge them £10, which was the rate for class 4 vehicles.
70.	It is true that that was before it was appreciated that there was a problem with the 1997 or 2000 Orders.  It appears that it was only while preparing for the inquiry that the Confederation appreciated that there was a problem with the levying of tolls on large buses under the 2000 order.  At the hearing of the inquiry the Confederation submitted that the Board was not entitled to levy tolls on large buses for the reasons discussed above and told the inspector that it was preparing an application for judicial review.  It was also submitted to him that, since the advertisement did not refer to large buses, operators of them might have been misled into believing that they had no interest in the proposals made by the board to the inquiry.  
71.	In the circumstances the confederation invited the inspector to adjourn the inquiry.  He declined.  He said this in his report:
“2.4	The submission relating to the lawfulness of the levying of tolls on large buses is not a matter for me.  As to the adjournment application, this was not renewed at the enquiry and, indeed, was expressly withdrawn by the representative of the objector on whose behalf the application had been made.
 2.5	I nevertheless considered carefully whether failing to adjourn the enquiry might prejudice operators of large buses who had not objected to the Board’s proposal.  Whether lawfully or not, these vehicles have been subject to a toll for using the bridge since its inception, a period of some 20 years.  In these circumstances, it was not credible, in my view, that operators of such vehicles would not have been alerted by the advertisement of the Board’s proposal to the fact that their interests were in issue in the proposal and therefore at the enquiry.  I was reinforced in the conclusion by the fact that 6 of the 7 objections to the proposal were made by bus and/or coach operators.  I concluded accordingly that it was neither desirable nor necessary to adjourn the enquiry”
There is, so far as I am aware, no evidence that any relevant bus operator thought that the proposals did not affect him.  Any such suggestion would have been, as the inspector put it, incredible.
72.	The inspector rejected the PSV operators’ objections.  He did so in these terms:
“6.7	I deal first with the objection relating to all PSVs, including but not therefore restricted to scheduled local bus services.  I have considered the claim that the fact that coaches and buses carry human cargo distinguishes them in some way from other commercial vehicles.  I am unable to accept this argument.  A decision whether to use the bridge in the course of a journey carrying passengers on a day trip to Scarborough or Whitby seems to me no different in character from a decision in relation to a goods vehicle of the same weight (and therefore in the same toll class) carrying vegetables across the bridge to Hull.  The toll payable for the use of the bridge is an alternative to the cost, including wages, fuel and vehicle wear and tear, or the longer drive to the next available crossing of the Humber to the west…”
73.	The inspector thus thought it right to include PSVs and therefore large buses.  It is to my mind quite clear from his report, however, that he did not intend to recommend any greater maximum than had been sought by the Board.  This can be seen from paragraph 6.10:
“I do not therefore accept that any reduction in the toll proposed for all PSVs is appropriate.  It follows that there is no purpose to be served by establishing a separate PSV toll class, as urged by the objectors.  …  Charging for PSVs by weight and number of axles seems to me to be fair, having regard to my conclusion above as to the essentially commercial nature of these operations in general.  … ”
74.	Although there is a reference in that paragraph to charging PSVs by weight and number of axles, I do not read the report as a whole as recommending a new maximum toll calculated by reference to the number of axles.  The inspector was considering and rejecting the objectors’ case that there should be a reduction in the “toll proposed”, which (as already stated) was £10 for all large buses on the basis that they should be treated as class 4 vehicles, as they had been in the past.  This is also clear from later paragraphs of the report in which the inspector considered the previous figures, namely an increase of over 40% from £6.50 to £9.20, in 1997 and an increase of 4.3%, from £9.20 to £9.60, in 2000.  He rejected the objectors’ suggestion that the ratio of cars to large buses should be 1:1.87, which (as he put it in paragraph 6.18) would result in a proposed toll of £4.67 (ie £2.50 x 1.87), as against the proposed non-discounted toll of £10.00.
75.	Finally, the inspector recommended “that the Secretary of State make a Tolls Order pursuant to Section 10 of the Humber Bridge Act 1971 to implement the proposals contained in the application of the Board dated 1 March 2001”.  He thus recommended an increase of the maximum toll for large buses to £10.  The Secretary of State considered the inspector’s report and issued a decision letter dated 25 March, which was three days after the date of the order but there can I think be no doubt that the order was intended to reflect the Secretary of State’s decision in the letter.  
76.	In the letter the Secretary of State referred to the Board’s proposals, to the objections of the PSV operators.  In paragraph 5 he expressly accepted the opinions of the inspector on the representations made by the bus operators.  In paragraph 6 he stated that he believed that the proposed application for judicial review should be treated separately from the 2002 Order and in paragraph 7 he recorded that the inspector recommended that the Secretary of State make an order in the terms applied for by the board.  The Secretary of State added in paragraph 8:
“On the basis of the evidence before him and having regard to Section 10 of the 1971 Act, the Secretary of State is satisfied that the proposed toll revisions are justified.  The Secretary of State has, therefore, decided to make the Order.”
77.	It is to my mind plain from the letter that the Secretary of State intended to make an order implementing the inspector’s recommendation that the Board’s proposals be adopted.  It follows that he intended that large buses be charged under class 4 at a maximum rate of £10, which was four times the £2.50 maximum toll for cars.  He plainly did not intend that they should be charged at a greater rate if they had more than two axles.
78.	How then did the 2002 Order come to be in the form in which it was, without any reference to large buses at all, even in the definition section?  It appears to me that the explanation can only be that, notwithstanding paragraph 6 of the letter, the draftsman was concerned about the possible application for judicial review.  However that may be, for the reasons I have given, it is clear that it was intended that large buses be charged under class 4.  I note in passing that, as I understand it, after the decision of the judge the Board continued to charge large buses at £10 and not at any greater rate.  That is consistent with the Board’s intentions throughout.
79.	The Secretary of State’s letter set out in paragraph 2 the “existing and proposed tolls” which included under class 4 “Goods Vehicle exceeding 7.5 Tonnes maximum weight with 2 Axles” with maximum tolls of £9.60 and £10.00 for existing and proposed tolls respectively.  That formulation was reflected in the 2002 Order as set out above.
80.	The question is whether in these circumstances it is permissible to construe the 2002 Order as authorising a maximum toll for large buses on the basis that they are to be treated as falling within class 4.  In my opinion, in the light of the principles identified above, it is permissible to do precisely that.  I have already expressed the view in paragraph 65 above that the 2002 Order as drafted makes no real sense.  It makes no sense to conclude that the Secretary of State intended to exclude large buses altogether.  Equally it makes no sense to conclude that the Secretary of State intended to treat large buses (but not small buses) as “goods vehicles” or, for the first time, to charge by reference to the number of axles.  The 2002 Order is ambiguous or obscure and, indeed productive of absurdity.
81.	In my opinion, the principles identified in Jones v Wrotham Park Estates, the Inco Europe case and the Spath Holme case are satisfied here.  It is permissible to have regard to the Secretary of State’s letter and the inspector’s report to which it refers, construed in their historical context, in order to resolve the ambiguity in the 2002 Order and to determine what sum it was intended should be included as maximum toll for large buses.  The answer is £10.
82.	In all the circumstances, I would hold that the court can be abundantly sure of the three matters referred to by Lord Nicholls in the Inco Europe case.  First, the intended purpose of the 2002 Order was to increase the maximum tolls across the board, including for large buses.  Secondly, if the order does not provide a maximum toll for large buses, that can only have been the result of an inadvertent, or perhaps incompetent or inept, failure to do so.  That is, to my mind, true even if (as is likely) the reference to “large bus” in the definition section was omitted deliberately because the draftsman cannot have intended that the Board should not be permitted to charge for large buses at all.  Thirdly, it is clear from the extraneous materials, which seem to me on the authorities to be legitimate aids to construction of the 2002 Order, that the substance of the provision which the Secretary of State intended to make (and would have made if he had appreciated that the wording chosen did not achieve it) is that the maximum toll for large buses was to be the class 4 toll of £10.
83.	In my opinion this approach is to be preferred to the view expressed by the judge that the maximum tolls for large buses should depend upon the number of axles.  In these circumstances I would dismiss the appeal against the judge’s refusal to grant the Confederation’s application for judicial review in so far as it related to the 2002 Order, but would hold that on the true construction of the order the maximum toll for all large buses is £10.
Conclusion
84.	I would dismiss the appeal and hold that the Board was entitled to charge a maximum of £9.20 under the 1997 Order, £9.60 under the 2000 Order and £10.00 under the 2002 Order.
Lord Justice Jonathan Parker:
85.	I agree.
Lord Justice Auld:
86.	I also agree.       

Order: Appeal Dismissed with costs; Leave to appeal refused.
(Order does not form part of the approved judgment)