Case No: CO/522/2002
Neutral Citation Number: [2002] EWHC 1720 (Admin)
IN THE HIGH COURT OF JUSTICE
QUEEN'S BENCH DIVISION
(ADMINISTRATIVE COURT)
Royal Courts of Justice
The Strand
London WC2

Date: Thursday, 4th July 2002
B e f o r e:

LORD JUSTICE ROSE

and

MR JUSTICE GIBBS

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THE DIRECTOR OF PUBLIC PROSECUTIONS

-v-

COLIN MEMERY

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Computer Aided Transcript of the Palantype notes of
Smith Bernal Reporting Limited, 190 Fleet Street,
London EC4A 2HD
Tel: 020 7404 1400
Official Shorthand Writers to the Court)
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MR R WHITTAM appeared on behalf of the CLAIMANT

MR N LEY  appeared on behalf of the RESPONDENT

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J U D G M E N T

1.	MR JUSTICE GIBBS: This is an appeal by way of case stated by the Director of Public Prosecutions against the decision of 
2.	His Honour Judge Kilfoyle and two lay justices at the Warrington Crown Court on 7th August 2001. 
3.	The decision of the Crown Court was made upon an appeal against conviction by the respondent, Colin Memery, from a decision of the magistrates' court on 21st July 2000. By that decision, the respondent had been convicted of driving a motor vehicle having consumed excess alcohol contrary to section 5(1)(a) of the Road Traffic Act 1988. The date of the offence was 11th November 1999. The respondent's appeal against conviction was allowed by the Crown Court. 
4.	The case stated by the Crown Court disclosed that they had found the following basic facts relating to the events of 11th November 1999: 
(1) On 11th November 1999 the respondent drove a motor vehicle on the public highway. 
(2) Having driven aforesaid the respondent was lawfully arrested and taken to the Widnes Police Station where he arrived at about 12.25 midnight the next day.
(3) On arrival and in answer to questions from the custody sergeant, the respondent told the custody sergeant that he was asthmatic and was on medication for it (ventalin). 
(4) At about 1.45 am, the respondent was required to provide two specimens of breath for analysis and was given the statutory warning of prosecution as required by section 7 of the Road Traffic Act. 
(5)The respondent complied with that request and exhaled into an intoximeter EC/IR (serial number 03611). 
(6) The said intoximeter, EC/IR purported to analyse the said specimens and printed out on paper the results as 49 and 46 milligrams of alcohol in 100 millilitres of breath. 
(7)At about 12.55 a.m. the custody sergeant read to the respondent paragraph B5 of Cheshire Constabulary form MG.DD/B. The sergeant then said to the respondent: “You can accept the reading or give blood.” The respondent declined to offer to provide a blood sample. 
(8) The intoximeter EC/IR are not made by Intoximeter Inc, but by Alcotec Inc. Intoximeter sell the EC/IR retail and service that device if so required by its purchasers. 
5.	There was a further important finding, to which I shall refer later, namely that EC/IR was purportedly approved by the Home Secretary. 
6.	In addition, in giving the judgment of the court, Judge Kilfoyle made the following further findings of fact: 
“We found the custody sergeant Prytherch to be a truthful, accurate, careful and reliable witness who we are sure would have noted anything and everything of significance and importance said to him, if said, by the appellant, in respect of medical or health matters; in particular, anything said directly and coherently to him by the appellant in respect of an alleged needle phobia. We are satisfied that unlike the appellant's direct and coherent information to the sergeant in respect of his asthmatic condition and the particular medication for that and like the custody sergeant's then full and accurate noting of that information and the questions and answers asked and given in respect of that medical aspect, the appellant did not bring any phobia or medical condition beyond or other than his asthmatic condition to the custody sergeant's attention and in particular, did not so tell the custody sergeant of any alleged claimed needle phobia. 
So in respect of facts, we have an appellant who, at 11.55 pm on that night, was stopped when driving up a one way street in the wrong direction, who admitted in evidence that his last drink in a friend's house where they were working having come back from a college together, working on notes it seems, his last drink there was about 7.30, he having taken his first drink that early evening about 5 o'clock. His friend continually, he said, topped up his glasses of straight Teachers whisky and he remembers getting to about, he says, maybe five such glasses. That is the factual position as far as the appellant's condition is concerned. It is right to say that he was co‑operative once the police officer stopped him, and throughout the proceedings.
Having dealt there with the purely evidential matter and found against the appellant, the respondent having proved to our satisfaction the contrary, as they have to, we move on therefore to the submissions made in respect of the reliability of the device employed in this procedure. We accept the evidence, as we were encouraged to do by both counsel, of the experts on both sides in this case, that mouth alcohol played no part in the consideration of the procedure in this case, since the factor of the time delay within parameters required means that no mouth alcohol could have been present in the sample. So in that sense we find therefore that the device used correctly and reliably registered mouth alcohol in that none was present, but we find later that the machine was incapable of measuring mouth alcohol had it been present.” 
7.	Whilst the Crown Court took the view on the facts that the breathalyser procedure was, on the face of it, correctly administered, and that mouth alcohol could not have been present in the samples taken, it also found that the device used either was not validly approved or could not reasonably have been approved by the Secretary of State. It made that finding on the basis that the device was incapable of distinguishing or sufficiently distinguishing between alcohol in the mouth and alcohol produced upon exhalation of breath from the lungs. It was not, to use the expression adopted by the judge in his judgment, “able to detect mouth alcohol when it was used in the field.” 
8.	It is convenient here to summarise the relevant statutory framework within which the charge against the respondent fell to be considered. The Road Traffic Act 1988 section 5(1): 
“If a person drives a motor vehicle on a road, after consuming so much alcohol that the proportion of it in his breath, blood or urine exceeds the prescribed limited, he is guilty of an offence.” 
9.	By section 7(1) of the Act it is provided as follows: 
“In the course of an investigation into whether a person has committed an offence under section 5 or section 6 of this Act, a constable may, require him - (a) to provide two specimens of breath for analysis by means of a device of a type approved by the Secretary of State.” 
10.	Section 8 provides so far as material: 
“(1) Subject to subsection 2 below, of any 2 specimens of breath provided ... that with the lower proportion of alcohol in the breath shall be used and the other shall be disregarded.
(2) If the specimen with the lower proportion of alcohol contains no more than 50 microgrammes of alcohol in 100 millilitres of breath the person who provided it may claim that it should be replaced by such specimen as may be required under section 7(4) of the Act and if he then provides such a specimen neither specimen of breath shall be used.” 
11.	Section 7(4) provides for replacement of the breath specimen by one of blood or urine. It is necessary here to cite the precise words of that subsection: 
“(4) If the provision of a specimen other than a specimen of breath may be required in pursuance of this section, the question whether it is to be a specimen of blood or a specimen of urine shall be decided by the constable making the requirement, but if a medical practitioner is of the opinion that for medical reasons a specimen of blood cannot or should not be taken the specimen shall be a specimen of urine. 
In respect of proceedings for an offence under section 5 of the Road Traffic Act 1988: 
	“evidence of the proportion of alcohol ... in a specimen of breath ... provided by an accused shall, in all cases, be taken into account and ... it shall be assumed that the proportion of alcohol in the accused breath ... at the time of the alleged offence is not less than the specimen.” [Road Traffic Offenders Act 1988 section 15(2)] 
12.	The statute plainly contemplates under section 7(1)(a) that it was to be the Secretary of State who would approve the type of device to be used for breath analysis. In exercise of his powers he approved as from 1st March 1998 as a means by which specimen of breath may be provided for analysis under section 7 the Intoximeter EC/IR for the use of the Police Force in England and Wales: see the Breath Analysis (No 2) Approval 1998 dated 25th February 1998. The documents are contained in the applicant's bundle at page 89, document 6. 
13.	Next I come to the reasoning, which includes certain further findings of fact, which led the Crown Court along a route which persuaded it to allow the appeal which was before it: 
“(9) The intoximeter EC/IR calculates the amount of alcohol by means of a fuel cell. When alcohol enters the cell, the latter substance alters the electric charge in the fuel cell and a computer calculates from the change in the charge the amount of alcohol in the breath specimen.
(10) To obtain an accurate analysis, the intoximeter EC/IR must analyse only alcohol in alveolar (deep lung) breath and not that in the upper respiratory tract. If it were to analyze alcohol in the throat, it would give an erroneously low reading. Whilst if it were to analyze mouth alcohol, it would give a falsely high reading.
(11) The EC/IR was one of 3 breathalysers approved by the Home Secretary in 1998. They were all approved on the basis that they complied with The Guide to Type Approval published by HMSO and the Quality Framework Document, copies of both of which were adduced in evidence before us and are annexed hereto.
(12) Accordingly the EC/IR was approved on the basis that it could detect mouth alcohol and when it did so, it would print out a message to that effect and automatically close down without giving an analytical result. Likewise if the higher reading exceeded the lower reading by 15%, then the message “Breath difference” is printed out. A breath difference of more than 15% calls into question the accuracy of the analysis. 
(13) The EC/IR's handbook was before the Home Secretary when he gave his approval. Page 7 was adduced in evidence and that states: `The sample [analysed] is one made up of alveolar breath and not tainted by alcohol from the upper respiratory tract of the subject' (i.e. mouth alcohol).”
14.	Paragraph 14 of the reasoning appears not to be material. 
“(15) The EC/IR uses special software to detect mouth alcohol from a certain profile. After its approval both the software and the alcohol profile were altered, with the result that the EC/IR serial number 03611 is not capable of detecting mouth alcohol....”
15.	I need not read the rest of the paragraph, for reasons which will appear later. 
“(17) Usually mouth alcohol (if the alcohol is not replenished between exhalations) will result in the difference between the 2 readings being more than 15% but this is not necessarily so. And when the readings do exceed 15% the EC/IR serial number 03611 did not always print out a “breath different message.” Thus on the test carried out on the EC/IR serial number 03611 by both prosecution and defence experts, if they had been for real, Professor Makin (one of the experts) would have been wrongly convicted of having excess alcohol in his breath; whereas in fact he had no alcohol whatsoever in his breath. He merely had mouth alcohol.”
16.	It is to be noted in passing that the exercise conducted by Professor Makin, to which reference has just been made, appears not to relate to any plausible situation which might have occurred in the field, still less in the present case. 
17.	Applying the law, as the Crown Court understood it to be, that reasoning and those findings of fact, it concluded that the intoximeter EC/IR was not a validly approved device or, if it was, then it was unreasonable for the Secretary of State to have approved it since it was a device which “detected mouth alcohol”, i.e, was liable to give a false reading by failing to distinguish mouth alcohol from the alcohol in the exhaled alveolar (deep lung) breath. It was essentially those conclusions which led the Crown Court to allow the appeal and quash the conviction. 
18.	Before the Crown Court the respondent further challenged a separate part of the procedure adopted by the police, namely the way in which the police officer expressed himself in offering the respondent the option of giving a blood or urine sample under section 8 of the Act. The court rejected this challenge and held that the procedure adopted was lawful. The respondent, through 
19.	Mr Ley, submits that the court's finding on this was wrong, and that accordingly, the intoximeter evidence should on that second ground also have been excluded. 
20.	Against the background of those facts and those issues, I come to the questions posed by the case stated. They are as follows: 
“(1) Was the correct procedure followed for the statutory option of giving blood when the alcohol level in the lower of the two breath specimens did not exceed 50 mg?” 
21.	This was the first and separate question. The remaining questions relate to the issue of approval. 
“(2) Was it Wednesbury unreasonable for us to have allowed an appeal in the circumstances where the respondent admitted driving and to providing 2 samples of breath, and where the agreed expert evidence was that the intoximeter EC/IR used to measure the said samples provided a correct and reliable reading that was higher than the prescribed limit?
(3) Was it Wednesbury unreasonable for us to have held that the intoximeter EC/IR serial number 03611 was not an approved device? 
(4) Was it Wednesbury unreasonable for us to have held that the Home Secretary would have been acting Wednesbury unreasonably in approving the said device?”
(5) Was it Wednesbury unreasonable for us to have held that the re‑approval by the Home Secretary of the said device was required after it had been altered in accordance with our finding of act?” 
22.	Before I proceed further, several preliminary matters need to be dealt with concerning the terms of those questions and the answers which this court is asked to provide. Nothing needs to be clarified at this stage about question 1. As I have said, it stands on its own and relates to the challenge mounted by the respondent to the procedure under section 8. 
23.	Questions 2 to 5, however, are inter‑related and need to be modified and reduced in scope. First, question 5 needs to be deleted. The reason for this was explained to the court at the outset of the hearing by both counsel. During the hearing before the Crown Court below, evidence appears to have been given that the intoximeter in question, after it had been approved, or purportedly approved, had several alterations made to it. 
24.	A submission was thus advanced on the respondent's behalf and considered separately by the Court, that by virtue of the alterations it was no longer an approved device, and could not become approved without being submitted for fresh approval. However, the Statement of Case and other documents prepared for this court suggest that there may not have been sufficient evidence of material alteration to the device before the lower court to justify that submission, nor to support the court's finding. 
25.	In order to test the extent and materiality of any subsequent alterations it would now be necessary to trawl through and analyse all the evidence. Neither party wished that process to be undertaken. It would be lengthy and an adjournment might be required. Thus, without conceding the point, Mr Ley, on the respondent's behalf indicated that it would not be relied on by him before this court. 
26.	However, the appellant for his part has indicated that in the event of the appeal succeeding, he would not be asking for the case to go back to the court below with a view to the conviction being restored. The alleged offence is now over three years old and apparently the disqualification has been served. Thus, on the face of it, the appeal might seem to have become academic, so that in the ordinary way, this court might not have been disposed to hear it. Counsel both ask that we should hear it since other appeals based on the same or a similar point are pending and are awaiting the outcome of this one. Under those circumstances, the court agreed that the appeal should proceed on the remaining grounds. 
27.	I therefore turn to questions 2 to 4. Questions 3 and 4 are essentially different ways of putting the same question. Question 3 refers to the Crown Court finding that the intoximeter was not an approved device. It was not, however, in dispute that the Secretary of State had in fact approved it. The argument was that the approval being unreasonable was invalid. The submissions in relation to questions 3 and 4 are identical, as Mr Ley realistically recognised in the course of argument. Thus question 3 adds nothing to question 4. For my part, however, I would re‑phrase question 4 to focus the issue more clearly, i.e: “Was it open to us to find that the Secretary of State in approving the device was acting unlawfully and/or Wednesbury unreasonably?” 
28.	That formulation allows this Court to consider fully the Crown Court's findings about the lawfulness or otherwise of the approval. If it was open to the Crown Court to make the finding that it did, then the intoximeter evidence was inadmissible and the appeal fails. If it was not open to them, then the appeal succeeds. The matters set out in question 2, whilst potentially relevant, do not in reality amount, in my view, to a separate question. I come now, therefore, to the questions themselves. 
	Question 1
29.	As already mentioned, it is the respondent who challenges the answer that the Crown Court gave to this question, the relevant finding having been against him. The respondent however cannot go behind the findings of fact on which it was based. Those are that the police officer did explain fully and in the prescribed manner the respondent's right to claim under section 8(2) of the 1988 Act to have breath samples replaced by a blood or urine sample. That explanation contained a reference to his right to give urine. It is said that the validity of the exercise was vitiated by the way in which the officer then put the matter in layman's terms. The officer in his evidence said that he could not recall exactly what he said, but in the course of the explanation he might have said: “You can accept the reading or give a sample of blood.” The officer did not say that he could recall the precise words. There was an acceptance by him that something along those lines would have been said. That appears from the transcript of the questioning of the officer, with which we have been helpfully provided.
30.	The Crown Court accepted for the purpose of their reasoning that those were the words said. The attack on the procedure is on the basis that effectively the opportunity to give urine was being taken from the respondent by the terms of the informal explanation; that the sole remaining option, that is to give blood, was improperly offered because of the asthmatic condition which had been disclosed by the respondent earlier. It is argued that the disclosure should have prompted medical opinion to have been taken before a blood test was offered as a substitute and, consequently, the procedure to which the respondent was entitled under section 8 was compromised. 
31.	For my part, I reject this argument for several reasons. The first and fundamental reason is that Mr Memery did not actually choose to exercise the option given to him by section 8(2), thus the stage had not been reached at which the issue of the respondent's medical condition arose for consideration. 
32.	In this regard the case can, and in my judgment should, be distinguished from two authorities cited to us: Johnson v West Yorkshire Metropolitan Police [1986] RTR 167 and Wade v DPP [1996] RTR 177. In each of those cases, the appellant had chosen to exercise the option. In each case, once the option had been exercised, matters were drawn to the officer's attention which gave rise to a duty on his part to consider whether there was a medical reason why blood should not be given. In each case it was held that the officer had failed to consider that question before blood was taken. In each case it was held that the officer's failure rendered the evidence of the blood sample inadmissible. 
33.	As I have said, in the present case the option was not exercised at all. Can it nevertheless be said that by reason of the terms of the police officer's explanation the option was not validly allowed to the respondent, in that the officer's words amounted to a restriction of the respondent's option to that of giving blood, but without the safeguard of permitting objection on medical grounds? 
34.	Here it is necessary to examine what was actually said by the police officer. His first words were to read the words which explained the respondent's statutory option. That they were read out is made clear at page 20 of the transcript. 
“As the specimen with the lower proportion of alcohol is in excess of the prescribed limit, but contains no more than 50 microgrammes of alcohol in 100 millilitres of breath, you may claim that it should be replaced by a specimen for a laboratory test. If you elect to provide such a specimen it will be of blood or urine, which in the case of blood, will be taken by a doctor. It is for me to decide which it will be unless a doctor is of the opinion that for medical reasons a specimen of blood cannot or should not be taken, in which case it will be of urine. If I decide the specimen shall be of blood, your only right to object and to give urine instead will be for medical reasons. 
You will be supplied with part of the specimen if you so require. The other part will be sent to a forensic laboratory for analysis. The results of the analysis of the laboratory specimen will replace the result of the breath test. Do you wish to provide a specimen for laboratory alcohol analysis?” 
35.	As I have said, the officer then gave an informal explanation which included the words “You can accept the reading or give blood.” 
36.	It seems to me that what the respondent was told plainly alerted him before he decided whether to exercise the option that if he did so he would have the right to object on medical grounds to giving blood. Then, if the objection was found justified, he could give urine. Whilst the officer felt it appropriate to give some further explanation beyond the words on the official pro forma, there was nothing obscure or technical about the words from the pro forma. In my judgment, there was nothing in the words used as a whole nor indeed in any part of them which could have pre‑empted consideration of any medical condition if the respondent were to exercise the option. Nor is there any material on which the justices could or should have found that the officer's words may have operated to dissuade the respondent from exercising his option. 
37.	The fact is that he did not exercise it. Had he done so, the very next words on the pro forma, which no doubt the officer would have used, were these: “Are there any medical reasons why a specimen of blood cannot or should not be taken by a doctor?” The respondent would plainly have had the opportunity to raise them. The fact that the respondent mentioned his asthmatic condition earlier on, after having been taken to the police station, does not, in my judgment, alter the position so as to render the procedure which I have described unlawful. The Crown Court was entitled to find that there was no obligation on the sergeant on the basis of the facts described to consider calling a doctor before indicating that the replacement sample was to be of blood. There was nothing which rendered the intoximeter evidence inadmissible on that ground. Accordingly, the respondent's challenge to this aspect of the Crown Court's findings fails. 
38.	I now turn to the other question as condensed and re‑phrased earlier in this judgment. The first objection which arises to the lawfulness of the approval was actually one advanced by the respondent before the Crown Court through Mr Ley, but rejected by it. Mr Ley renews the objection before us. It relates to the terms of approval which say that the intoximeter device is manufactured by Intoximeter Inc. of Saint Louis, Missouri whereas, in fact, it is made by Alcotec Limited and indeed some components by British Oxygen. Intoximeter Limited do no more than market and service it. There is only one device known as the intoximeter EC/IR. The approval document identifies that device. The fact that the document goes on to say that it is manufactured by Intoximeter Inc. of Saint Louis in Missouri creates no ambiguity in the description of the device being approved. 
39.	The same point was considered by this court in Chief Constable of Northumbria v Browne [1986] RTR 113. In that case the justices had acquitted the defendant on the ground that the company named as the manufacturer of the device in the approval order did not exist. At the conclusion of his leading judgment Watkins LJ said: 
“I admire the ingenuity of those submissions. I think they are, however, fallacious. The Secretary of State was called upon to do no more by the Act of Parliament than to approve, as he states in his Order, a type of device. By the material parts of the Schedule to which I have already referred he did, in my judgment, do precisely that. The fact that he went on to refer to the manufacturers of those devices does nothing, by an error in the description of one of the companies, to invalidate the approval of the device. 
I would allow this appeal.” 
40.	I respectfully adopt his reasoning; the Crown Court was right to reject the submission. 
41.	I come now to the matter which persuaded the Crown Court to allow the respondent's appeal, namely the fact that neither the type of device approved nor the individual device used was capable of satisfactorily detecting mouth alcohol. That being the position, in the court's view the machine could not have been lawfully approved since the approval documents make it clear that the capacity to detect the alcohol was an essential requirement of the device. This submission in one form or another has been made and analysed in several decisions to which I shall come shortly. 
42.	Before doing so, it is necessary to summarise relevant aspects of the procedure adopted by the Secretary of State for approving the type of device and the procedure laid down for subsequently checking the device. 
43.	“A Guide to Type of Approval Procedures for Evidential Breath Alcohol Testing Instruments used for Road Traffic Law Enforcement in Great Britain”, issued by the Home Office and Forensic Science Service dated October 1994, contains a description of the technical requirements to be met for consideration of type approval for new Evidential Breath Testing Instruments, their method of operation and the method of testing prior to submission for the Secretary of State for consideration of type approval. 
44.	This is a functional requirement for products which may be manufactured by any process. Chapter 2 (type procedure) provides by paragraph 2.6 that when the assessments at Annex A and B have been satisfactorily completed and a full report issued, the manufacturer shall supply free instruments to the breath alcohol units of the Forensic Science Service together with the relevant reports. The assessment made there shall be for tests involving response to alcohol vapour samples as set out in Annex C. One such test is set out at paragraph C11 of that guide. 
“The effect of the presence of alcohol in the upper respiratory tract. A test shall be carried which is designed to simulate the effect on the instrument of mouth alcohol or alcohol vapour in the dead-space of the upper respiratory tract generated from stomach contents (regurgitation or eradication). No result shall be recorded and a suitable message shall be given by the instrument. This test shall be carried out twice. 
A breath sample containing mouth alcohol is likely to exhibit an initial rapid rise in ethanol concentration followed by a negative rate of change of ethanol.” 
45.	The test under C11 for the purpose of type of approval is carried out by a machine not a human being. It has been described as a “robotic” test. 
46.	In addition to the type approval tests, each device must be checked prior to despatch to customers to ensure that the performance of the manufactured instrument is comparable with that required by the type approval procedure. These individual tests are carried out under “The Quality Framework Document For Evidential Breath Alcohol Testing Instruments.” The tests required are set out in paragraphs 4.2 to 4.29 of that document. 
47.	Those tests do not require the tests set out in paragraph C11 of the type of approval procedures guide to repeated on each machine. 
48.	Criticisms are made of the efficacy of these procedures as they relate to mouth alcohol. The criticisms were accepted and adopted by the Crown Court having, as they were entitled to, heard expert evidence. They found in effect that the machine could not detect mouth alcohol sufficiently or at all because the robotic tests laid down were ineffective or at least not as effective or sensitive as tests carried out on human subjects or “biological tests” as they were described. 
49.	Mouth alcohol, if present, could give an artificially high reading. However, if the machine in recording a breath sample was unable to detect mouth alcohol, there was a further safeguard in that two breath samples were always taken; the presence of mouth alcohol in one of them leading to an abnormally high reading would be revealed by the disparity of the two readings, and the machine should be capable of detecting this. The Crown Court found that the individual machine in this case, even if it did detect this disparity, did not always print out the required message, namely the “breath different message.” 
50.	The factual position therefore, as the justices on the face of it were entitled to find, can be summarised thus: 
(a) the detection of mouth alcohol was a functional requirement of the device; 
(b) the type of device in the course of its approval process was subjected to tests whose purpose was to enable the device to meet that functional requirement. 
(c)the tests were not adequate to ensure that the type of device in question always met the functional requirement, nor were they adequate to ensure that the individual machine met that requirement at any rate in the circumstances in which the expert witnesses themselves tested it. 
51.	However, that having been said, there were further aspects of the device and its operation which were indisputable and which the Crown Court either did or should have borne in mind. 
52.	(i) There was no suggestion that (provided the presence of mouth alcohol was sufficiently allowed for) the device was other than accurate in measuring expelled air from the lungs. 
53.	(ii)The procedure for approving the device included considered tests designed to safeguard against the presence of mouth alcohol in a sample albeit that the Crown Court found that these tests on the experts' evidence were deficient. 
54.	(iii)There were procedural safeguards quite apart from the function of the device itself to guard against the false reading being admitted in evidence. For example, there was the option exercisable under section 8 of the Act to have a blood or urine sample taken. Further the correct procedure, followed in the present case, provided for questions to the suspect as to whether alcohol or other substances had been consumed in the previous 20 minutes. If the answer revealed substance consumption which might affect the procedure, the officer was required not to undertake further questioning, save in accordance with the Police and Criminal Evidence Act 1984. 
55.	(iv) In the present case the respondent had answered no to each such question. 
56.	(v) Further the respondent's intoximeter readings could not (on the unanimous expert evidence) in fact have been affected by the present of any mouth alcohol. 
57.	Against that background, I come to the relevant case law. 
58.	In R v Skegness Magistrates ex parte Cardy [1985] RTR 49, the House of Lords considered the issue of type of approval amongst other things. In the speech of Goff LJ, he confirmed the defendant's right to challenge the accuracy of an individual device, pointing out that the fact that the machine was approved did no more than create a presumption that it was accurate. 
59.	He went on as follows at page 61 letter E: 
“In any event, it is one thing to challenge the reliability of the particular device upon which a defendant's breath was tested at the relevant time, which may be entirely proper in the circumstances of a particular case, and another thing to attempt to challenge the reliability of Lion Intoximeter 3000 devices generally. If there are those who have reasons to believe that Lion Intoximeter 3000 devices are generally unreliable, they are in truth saying that they should never have received the approval of the Secretary of State, or that the Secretary of State should withdraw his approval from them. They should therefore address their representations to the Secretary of State. But, so far as cases such as these are concerned, the fact is that the Lion Intoximeter 3000 device is and has been since 19 April 1983 an approved device for the purposes of the Act and, so long as that state of affairs continues, it is, in our judgment, wholly immaterial to mount a challenge to the general reliability of these approved devices in individual prosecutions brought under the Act.” 
60.	The presumption that Goff LJ had referred to was that the proportion of alcohol in the relevant specimen was no less than the proportion of alcohol in the breath at the time of the offence. In the event of the assumption being challenged by the defendant, the justices have to be satisfied on relevant evidence that the reading provided by the machine is one on which they can rely, the burden being on the prosecution: Cracknell v Willis (1988) 1 AC 450 at page 467 C-F Lord Griffiths. 
61.	In two appeals heard together by this court in November 2001, issues arose which were very similar to those in the present case. The decision was DPP v Browne and DPP v Teixeira (unreported, judgment 16th November 2001). In both cases an attack was mounted before magistrates by means of expert evidence on the ability of the device to detect mouth alcohol. In neither case was there any evidence that the defendant could have had mouth alcohol present such as to interfere with the accurate reading. In each case the justices accepted that the machine was defective in its ability to detect mouth alcohol and dismissed the information on that ground. After an extensive review of the law and authorities Cresswell J concluded at paragraph 48(1) of his judgment: 
“Magistrates are only concerned with the particular intoximeter device used (for example in Mr Brown's case EC/IR instrument number 01384). It is thus no part of their function to consider whether the intoximeter EC/IR should have received the approval of the Secretary of State.” 
62.	Pill LJ at paragraph 55 said: 
“The Magistrates were not entitled to conclude that the general presumption of reliability had been rebutted by the evidence of Professor Makin.” 
63.	He went on:
“The presumption that the device is reliable had not been challenged by relevant evidence in that, in the absence of mouth alcohol, the defect alleged was not relevant to the facts of this particular case. On the evidence, the presumption in section 15(2) was not displaced in either case by the expert evidence in the manner alleged by the defendant and accepted by the Magistrates. 
I agree with Cresswell J as to the approach to be adopted by magistrates when asked to consider evidence of the kind called in these cases.” 
64.	In a very recent Scottish case, the Sheriff's Court was confronted with a challenge to the reliability of the device on similar grounds and on the basis it would appear of similar evidence to those found here. The sheriff rejected the argument and convicted the motorist Mr Brown, who appealed to the High Court of Justiciary. The appeal decision is, as far as is known, unreported. Brown v Procurator Fiscal 8th March 2002 256/02. 
65.	It is persuasive authority because of the detailed judgment of Lord Cameron of Lochbroom and further because it considered the Crown Court's judgment in the present case, that of Mr Memery. In dismissing the appeal Lord Cameron said a number of things pertinent to this present case. He began by quoting the Sheriff's conclusions: 
“The sheriff went on to say this: 
`It seems to me therefore that what the Secretary of State approved was a device which was capable of quickly and accurately measuring alcohol in the blood by means of analysing alcohol in deep lung breath. It required to be capable of discriminating deep lung breath from other substances (interfering substances) and from mouth alcohol. It required in certain circumstances to register error messages such that analysis of specimens of breath outwith certain parameters could not found a prosecution.
During the lengthy, rigorous and apparently dynamic type approval procedures, it was recognised that the requirement to detect mouth alcohol posed difficult and complex problems for the device. However, it was also recognised that mouth alcohol or regurgitated or eructated alcohol would rarely, if ever, occur over 2 samples. Safeguards were incorporated into the device (the breath difference) and in the legislation (section 8(2)) to obviate the risks of an inaccurate or unreliable analysis resulting in injustice.
There is no suggestion in the evidence nor was there any such submission that the device was in any other sense deficient in its functioning'
That is to say the sheriff was satisfied that the device was functioning as a device of the type approved in terms of paragraph 3 of the Schedule to the Breath Analysis Devices (Scotland) Approval 1998 at the time that the appellant provided the samples of breath on 3 January 2000. The sheriff declined to follow the decision in Memery on the ground that the court did not appear to have had the opportunity of fully analysing the context in which approval is considered and given nor the safeguards against injustice which are inherent in the device itself and the legislation. In our opinion, he was right to do so.”
66.	The judge went on to point out in detail why it was that the device met the requirements for approval as an evidential testing instrument. He continued: 
“In these circumstances we agree with the sheriff the that the decision in Memery is flawed in so far as it appears to suggest that inconsistency in reacting to biological tests for mouth alcohol must lead to the conclusion that the device was not functioning and never had functioned as an evidential breath testing instrument approved by the Secretary of State. 
Accordingly, we agree with the sheriff that fact that it may have been demonstrated that the device reacted inconsistently to mouth alcohol when tested biologically did not deprive it of type approval nor did it demonstrate that on 3 January 2000 it did not function as a device in relation to which the statutory requirement could be made of the appellant in terms of section 7(1)(a) of the 1988 Act.”
67.	The factual strand common to all these cases is that in none of them on the evidence is there any causal connection between any defect in the devices' ability to detect mouth alcohol and the reliability of the reading presented in evidence. 
68.	I turn therefore, finally, to Boddington v British Transport Police (1999) 2 AC 143, a case relied upon by Mr Ley. That case concerned a criminal prosecution and conviction against Mr Boddington for smoking a cigarette in a train contrary to railway bye laws under the Transport Act 1962. The issues raised by the case necessitated consideration by the House of Lords. The House of Lords found that the stipendiary magistrate erred in finding that he had no jurisdiction to rule on the validity or otherwise of the byelaw in question. (It also held that the byelaw was valid). 
69.	Mr Ley cited extensively from speeches in the case; the most important passages are as follows in the speech of Lord Irvine at page 152 F: 
“The question of the extent to which public law defences may be deployed in criminal proceeding requires consideration of fundamental principle concerning the rule of law and fairness to defendants to criminal charges in having a reasonable opportunity to defend themselves. However, sometimes the public interest in orderly administration means that the scope for challenging unlawful conduct by public bodies may have to be circumscribed. 
Where there is a tension between these competing interests and principles, the balance between them is ordinarily to be struck by Parliament. Thus whether a public law defence may be mounted to a criminal charge requires scrutiny of the particular statutory context in which the criminal offence is defined and of any relevant statutory provisions. That approach is supported by authority of this House.” 
70.	At page 161 C of the same speech: 
“However, in approaching the issue of statutory construction the courts proceed from a strong appreciation that ours is a country subject to the rule of law. This means that it is well recognised to be important for the maintenance of the rule of law and the preservation of liberty that individuals affected by legal measures promulgated by executive public bodies should have a fair opportunity to challenge these measures and to vindicate their rights in court proceedings. There is a strong presumption that Parliament will not legislate to prevent individuals from doing so: 
`It is a principle not by any means to be whittled down that the subject's recourse to Her Majesty's courts for the determination of his rights is not to be excluded except by clear words: Pyx Granite Co. Ltd v. Ministry of Housing and Local Government [1960] A.C.260, 286 per Viscount Simmonds.'“
71.	At 162 G: 
“In my judgment only the clear language of a statute could take away the right of a defendant in criminal proceedings to challenge the lawfulness of a byelaw or administrative decision where his prosecution is premised on its validity.”
72.	In the speech of Lord Steyn at page 173 F:
“There is no good reason with defendant in a criminal case should be precluded from arguing that a byelaw is invalid where that could afford him with a defence. Sometimes his challenge may be defeated by special statutory provisions on analogy with the decision in Reg. v. Wicks [1998] A.C. 92. The defence may fail because of the relevant statutory provisions are held to be directory rather than mandatory. It may be held that substantial compliance is sufficient. But, if an issue as to the procedural validity of a byelaw is raised, the trial court must rule on it.”
73.	On the basis of Boddington, Mr Ley submits that R v Brown and Teixeira was wrongly decided since this court in that case did not have regard to Boddington. It is submitted that if it had had regard to that decision, it would have declared itself ready to permit the appellants to rely on the public law challenge to the Secretary of State's purported approval of the device, and had it done so, would have found that the Secretary of State's approval of the device was invalid or unlawful. The same argument must by implication apply to the Scottish case. 
74.	In my judgment, those submissions cannot here be sustained. It is true that the Crown Court was prepared to take the route held to be permissible and proper on the face of it in Boddington, namely to entertain a challenge to the approval of the intoximeter device on a public law basis. But in my judgment the approach of this court in Brown and Teixeira and the 
75.	Scottish Appeal Court in Brown v Procurator Fiscal are consistent with the principle in Boddington. What the court effectively was doing in each of those cases was considering comprehensively in the broad legislative context whether it could have been intended by Parliament that the defendants in those cases should be able to challenge the approval of the device in question. In each of the cases the answer was no. 
76.	I have also given attention in this case, in the broad legislative context, to whether the Crown Court was permitted to rule on the Secretary of State's approval of the device. In my opinion, the answer in the present case should also be no. The reasons for this view are apparent from the passages already cited and are principally as follows: 
(a) The point at issue is one of admissibility of the relevant evidence, i.e, of the intoximeter reading. 
(b) The reliability of the reading in a particular case is always open to challenge by admissible evidence and in the event of challenge it is for the prosecution to prove its actual reliability. 
(c) In the light of the legislative context when properly analysed, Parliament, in my view, cannot have intended every defendant to have the right to challenge the lawfulness of the Secretary of State's approval of the evidential device. 
(d) In any event, in the context of the reliability of the machine and the provisions of the statutory scheme when looked at as a whole, including all the procedural safeguards relating to the possibility of inaccurate readings due to mouth alcohol, the approval of the device cannot be described as irrational. 
(e) In the present case, the ability of the device to detect mouth alcohol was wholly irrelevant to the reliability of the evidence it provided against the respondent. Its accuracy in that context was not doubted by any of the experts. 
77.	I turn therefore to the question posed: “Was it open to us to find that the Secretary of State in approving the device was acting unlawfully and/or Wednesbury unreasonably”, and to that question I would answer no. 
78.	For all those reasons, for my part, I would allow this appeal. However, for reasons already explained, I would grant no further relief. 
LORD JUSTICE ROSE: I agree. 
MR WHITTAM: My Lord, there is no consequent applicant on behalf of the Director, given the age of the case and the fact that the respondents were publicly funded. 
LORD JUSTICE ROSE: Thank you. 
MR LEY: My Lord, in view of the last comment of my learned friend, I would seek what used to be called a legal aid taxation. I believe it is now a public funded assessment. 
LORD JUSTICE ROSE: Yes, you may have that Mr Ley. 
(The Court Adjourned)