Case No: B3/2003/0420
Neutral Citation Number: [2003] EWCA Civ 1844
IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM THE NEWCASTLE COUNTY COURT
(HHJ HEWITT)
Royal Courts of Justice
Strand, 
London, WC2A 2LL

Wednesday 17th  December 2003
Before :

THE PRESIDENT OF THE FAMILY DIVISION
LORD JUSTICE BROOKE 
and 
LORD JUSTICE LATHAM

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Between :

	KATHLEEN CUMMING & OTHERS	Appellants	
	- and -		
	CHIEF CONSTABLE OF NORTHUMBRIA POLICE	Respondent	

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(Transcript of the Handed Down Judgment of
Smith Bernal Wordwave Limited, 190 Fleet Street
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Mr David Wilby, QC & David Callan (instructed by Thompsons) for the Appellants
Mr Simon Freeland, QC & Toby Wynn  (instructed by The Chief Constable of Northumbria) for the Respondent
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Judgment
Lord Justice Latham: 

1.	Between the 15th and 18th June 1999, the appellants were separately arrested by the Northumbria Police on suspicion of perverting the course of justice.  They were taken to the police station, questioned and released.  They were all innocent.  They were of good character; and there is no doubt that their arrest caused each of them distress, fear and humiliation.  In these proceedings they claim damages, including exemplary damages, for wrongful arrest and false imprisonment.  On the 27th January 2003, HHJ Hewitt dismissed their claims.  He held that the police officers in question had acted in good faith, had, objectively, reasonable grounds for suspecting that each of the appellants had committed an arrestable offence, namely perverting the course of justice, and that their decision to arrest was a proper exercise of the police officers’ discretion.   The appellants appeal on the grounds that the judge was wrong in both latter respects.
2.	There was little dispute about the background facts.  The appellants were employed at the relevant time by the South Tyneside Metropolitan Borough Council in its Warden Services department in South Shields.  In particular they were concerned with monitoring the recordings made by the town’s closed circuit television cameras.  The recordings were held on two types of tape.  The first was what was known as the “spot” tape for each camera, also known as the “red spot” tape, because it was always identified on its spine in red ink.  The second was what was known as the “multiplex” tape which held the recordings from all the cameras.  In the event of any incident, the warden who was monitoring the relevant “spot” tape at the time would report the matter to the police and ensure that the “spot” tape was made available for the police if the police required it for forensic purposes.  The “spot” tape could then be used as evidence with the master tape being available to check the reliability and integrity of the “spot” tape.  This system was clearly an important tool in the police armoury for the purposes of keeping public order and the prevention or detection of crime.  
3.	At 11.10 a.m. on Saturday 22nd May 1999, a colleague of the appellants, Alan Starbuck, saw on one of the video screens, a young man trying the doors of cars.  He contacted the police in accordance with the practice to which I have already referred, as a result of which Police Constable Ward went to the scene and arrested a young man.  On Tuesday 25th May, the same police officer went to the video room in order to view and take possession of the relevant “spot” tape which should have run from 1.00 a.m. on the 22nd May to 1.00 a.m. on the 23rd May.  The tape which she was handed was unusual in two respects.  First, it had been recorded over: it commenced with a recording which started according to the timer, at 16.19 on the 22nd May, continued to 1 a.m. on the 23rd and then returned to the events of the morning commencing at 11.19, that is a few minutes after the relevant incident.  Second, as the judge found, the writing on the spine, invariably in red, was in blue, which made the police officer suspect that it was a copy.  Police Constable Ward then asked to see the “multiplex” tape only to find that this tape had also, in her words, been “tampered with”; and the incident was no longer visible.
4.	Understandably, both the police and the appellants’ employers were extremely concerned with what appeared to have been deliberate interference with the tapes.  The over taping on the “spot” tape could perhaps have been accidental; but the co-incidence of the removal of the relevant incident from the “multiplex” tape suggested a deliberate attempt to destroy the evidence of a crime.  A meeting of the police and the appellants’ employers took place on the 27th May at which it was decided that the employers would investigate, giving the appellants and their colleagues an opportunity to come forward and give their accounts.  The judge found that the police reasonably believed that the employers intended to interview each of the staff individually.  Unhappily, no such interviews took place.  
5.	In early June, the police were told by Mr Marriott on behalf of the employers that their investigation had not borne fruit.  Detective Sergeant Richards was put in charge of the police investigation, assisted by Police Constable Ward who had been involved in the original incident and Police Constable Abdullah.  They made inquiries to determine whether or not there was any link between the young man who had been arrested, and any member of staff.  No such link could be found.  They then compiled from the duty rota a list of those employees who would have had the opportunity either to have been involved in the over taping and tampering or who might have been present and therefore assisting when that happened.  By this and other means, they eliminated all members of staff apart from the appellants and Mr Starbuck.  The police officers gave evidence, which the judge accepted, that much time was taken examining the records of telephone calls made during the relevant period and in enquiries of the technical unit at the Force Headquarters, the Forensic Science Laboratories at Wetherby and at Victoria in London, as to whether a time could be established at which the tapes had been tampered with.  Somewhat surprisingly, they obtained no assistance from those sources, a point to which I shall return later.
6.	Detective Sergeant Richards and Police Constable Ward together with Police Constable Abdullah therefore decided to arrest the five appellants and Mr Starbuck.  Having heard the evidence of Detective Sergeant Richards and Police Constable Ward, the judge concluded that the reason for deciding to arrest them, as opposed to taking any other form of action, such as seeking to interview them voluntarily, was that the police wanted to exert maximum pressure to get the confession that had eluded management.  The appellants were arrested at different times between the 15th and 18th June, taken to the police station and interviewed under caution.  Although it should be said that the arrests and interviews were conducted in the main in a civilised and restrained way, the appellants were inevitably shocked.  It is accepted that they were all innocent and upstanding citizens.  Their claim for damages is based upon the psychiatric consequences to each of them of their experience.
7.	Ultimately, the police were satisfied that the “spot” tape was the original tape, and gave a reliable indication of when the “spot” tape was recorded over, namely 16.19 on the 22nd May.  That coincided with the time that Mr Starbuck was on duty.  He was interviewed on the 21st July and eventually admitted that he had inadvertently rewound the “spot” tape and recorded over it.  He denied having tampered with the “multiplex” tape.  This aspect of the matter therefore remains unresolved.
8.	The judge directed himself that he should ask the three questions formulated by Woolf LJ in Castorina –v- Chief Constable of Surrey [1996] LG Rev Rep 241 at page 249:
“(a)	Did the arresting officer suspect that the person arrested was guilty of the offence;
(b) 	were there reasonable grounds for that suspicion;
(c)	did the officer exercise his discretion to make the arrest in accordance with Wednesbury principles”
9.	As to the first question, the judge said:
“It is argued for the claimants that the police did not in fact suspect, taking each individual separately, that that individual was guilty of that offence.  On the basis of what was known at the time of the arrest, it is argued that only one or possibly two persons could have been involved: therefore either four or five of those arrested must have been, as a matter of logic, known to have been innocent.  The police, it is said, had no suspicion as to who had been involved with the tape or tapes and simply performed a blanket arrest for reasons of expediency, in other words to get a confession.  Whilst Mr Callan’s argument has a certain logical attraction, it fails because it is divorced from the reality of everyday policing in general and this case in particular.  Although this case is somewhat unusual because of the numbers involved, it is not unusual for an arresting officer to suspect a number of persons of committing an offence whilst at the same time appreciating that not all whose suspected  will prove to be involved.  As stated above, the answer to this first question depends on the court’s finding of fact as to the officer’s state of mind.  Having heard the testimony of D. Sgt. Richards and P.C. Ward I am satisfied that, whilst keeping an open mind as to the numbers of those involved, they were entitled to and did suspect that one or more of the 6 had deliberately and knowingly interfered with the tapes possibly with the assistance or connivance of others.”
10.	As to the second question, he rejected the submission that there were no reasonable grounds to suspect that the offence of perverting the course of justice had been committed.  In particular he rejected the argument that obvious lines of enquiry had not been pursued.  He accepted the evidence called on behalf of the appellants which showed that it was not difficult to establish that the “spot” tape had been recorded over at 16.19 on the 22nd May, as indeed the tape itself indicated, and that this did not require any specialist expertise such as that the police had been seeking.  It was said that if this timing had been appreciated before the decision to arrest, three out of the five appellants would have been eliminated as they worked on different shifts.  The judge, however also accepted that the police did not believe that the “spot” tape was the original tape because of the colour of the writing on its spine.  He was impressed by the evidence of the officers themselves when they were asked about this.  The suspicion as to its being a copy tape was indeed held by others.  He accepted that in the result the police had not with hindsight asked the right agencies the right questions.  But he concluded that the police nonetheless had reasonable grounds to suspect that one or more of the six had had some involvement in what had happened which was sufficient to justify their arrest as a matter of law.
11.	He was however concerned as to whether or not the decision to arrest was one which a reasonable police officer in possession of the facts could properly have taken.  He was understandably influenced by the fact that each of the appellants was a respectable person who had worked closely on a day to day basis with the police and would have been likely to co-operate with the police enquiries.  But he took the view that even though he considered that the decision was misjudged with the benefit of hindsight, the decision could not be categorised as perverse bearing in mind the fact that the police believed that each had been given an opportunity by the employers to give an account which would identify who was to blame but that that form of voluntary enquiry had produced no result.  It was in this context that he concluded that the police wanted to exert maximum pressure to see whether they could get a confession by using the power of arrest.  He accordingly determined that the police could legitimately have concluded that there was a greater likelihood that the appellants and Mr Starbuck would respond truthfully to questions if they were placed under arrest than if they were questioned without arrest.
12.	Mr Wilby, QC on behalf of the appellants,  accepts that the judge was right to ask the three questions posed by Woolf LJ in Castorina.  He does not challenge the judge’s conclusion that the police genuinely believed that they were entitled to arrest the appellants on suspicion of perverting the course of justice.  But he submits that they had no reasonable grounds for that suspicion.  He referred us to the following passage in the judgment of Sir Frederick Lawton in Castorina at page 460:
“Suspicion by itself, however, will not justify an arrest.  There must be a factual basis for it of a kind which the court would adjudge to be reasonable.  The facts may be within the arresting constable’s own knowledge or have been reported to him.  When there is an issue in a trial as to whether a constable had a reasonable cause, his claim to have had knowledge or to have received reports on which he relied may be challenged.  It is within this context that there may be evidential issue as what he believed to be the facts.  But it would be for the court to adjudge what were the facts which made him suspect that the person he arrested was guilty of the offence which he was investigating.”
This passage was referred to by Lord Hope in O’Hara –v- The Chief Constable of the Royal Ulster Constabulary [1997] AC 286 at page 300.  Although Lord Hope did not comment on it, the fact that he cited it is, in Mr Wilby’s submission, tacit support for the proposition that there must be a proper factual basis for a suspicion to justify an arrest.
13.	He further submits that this statement of principle accords with the provisions of Article 5(1)(c) of the European Convention on Human Rights which provides, so far as relevant:
“1.	Everyone has the right to liberty and security of person.  No one shall be deprived of his liberty save in the following cases and in accordance with a procedure prescribed by law:
…..
(c) 	The lawful arrest or detention of a person effected for the purpose of bringing him before the competent legal authority on reasonable suspicion of having committed an offence ….”
14.	He has referred us to the judgment of the European Court of Human Rights in Fox, Campbell and Hartley –v- United Kingdom (1990) 13 EHRR 157, where the court at paragraph 32 stated:
“The “reasonableness” of the suspicion on which an arrest must be based forms an essential part of the safeguard against arbitrary arrest and detention which is laid down in Article 5(1)(c).  The court agrees with the Commission and the government that having a “reasonable suspicion” presupposes the existence of facts or information which would satisfy an objective observer that the person concerned may have committed the offence.  What may be regarded as “reasonable” will however depend upon all the circumstances.”
15.	He submits that there were no facts which could properly be said to have given rise to a reasonable suspicion that any of the appellants individually had committed the offence of perverting the course of justice.  They were all of good character.  None of them had any known link with the suspected offender.  The most that could be said was that each of them had had the opportunity to commit the offence.  He submits that opportunity cannot amount to a fact sufficient to found a reasonable suspicion.
16.	His next submission is that, even if the judge was not wrong to answer the second Castorina question as he did, he was wrong to conclude that the decision to arrest was Wednesbury reasonable.  First, he submits that the police failed to take into account the fact that they were dealing with people of good character who had worked closely with the police in the past and who could therefore be expected to co-operate fully with any police investigation by answering questions voluntarily.  He referred us, in particular, to the interview of the appellant Kathleen Cumming where she expressly made the point that she would have been willing to have attended the police station to answer questions without the need for arrest.  Second, he submits that the judge was not entitled to conclude that the reason that the police decided to arrest the appellants was that there was a greater likelihood that they and Mr Starbuck would respond truthfully to questions if they were placed under arrest than if they were questioned without arrest.  That was not the case that had been pleaded, and it was not the evidence of either Detective Sergeant Richards or Police Constable Ward, the two police officers who gave evidence.  Further the interviews themselves were conducted in a manner which suggested that the police simply wanted information, and were inconsistent  with the form of interrogation to be expected of a suspect.
17.	Third, in a late written submission, he submits that the third Castorina question has to be answered in the context of the European Convention on Human Rights.  He has referred us to R –v- Ministry of Defence ex parte Smith [1996] QB 517, in which Sir Thomas Bingham MR stated, at page 554:
“Mr David Pannick [for the applicant] submitted that the court should adopt the following approach as to the issue of irrationality:
“The court may not interfere with the exercise of an administrative discretion on substantive grounds save where the court is satisfied that the decision is unreasonable in the sense that it is beyond the range of responses open to a reasonable decision maker.  But in judging whether the decision maker has exceeded this margin of appreciation the Human Rights context is important.  The more substantial the interference with Human Rights, the more the court will require by way of justification before it is satisfied that the decision is reasonable in the sense outlined above.”
This submission is in my judgment an accurate distillation of the principles laid down by the House of Lords in R- v- Secretary of Sate for the Home Department ex parte Bugdaycay [1987] AC 514 and R –v- Secretary of State for the Home Department ex parte Brind [1991] 1AC 696.”
18.	He has also referred us to the judgment of Simon Brown LJ in R –v- Secretary of State ex parte Turgat 28th January 2000 CA where the Lord Justice said:
“I therefore conclude that the domestic court’s obligation on an irrationality challenge in an Article 3 case is to subject the Secretary of State’s decision to rigorous examination and this is done by considering the underlying factual material for itself to see whether it compels a different conclusion to that arrived at by the Secretary of State.  Only if it does will the challenge succeed.”
19.	He submits that the right to liberty is so fundamental that any discretionary decision to arrest must be subjected to close scrutiny of the kind referred to by Simon Brown LJ.  It can only be justified if it is for a proper purpose and there is no other sensible means of achieving that purpose, without infringing the right to liberty of the person arrested.  In his submission, the judge was accordingly wrong to approach the case on what might be called classic Wednesbury principles; if he had asked the right question, in accordance with Convention principles, he must, on the facts, have come to the conclusion that the purpose to be served, namely seeking to obtain the truth from those arrested, could sensibly have been achieved by asking them to attend voluntarily for interview; and accordingly arrest was a disproportionate response with the result that the exercise of the discretion to arrest was irrational and unlawful.
20.	Mr Freeland, QC on behalf of the respondent, submits that the judge was plainly right for the reasons that he gave.  As to the appellants’ attack on the judge’s answer to the second Castorina question, he submits that the starting point for determining whether or not there were reasonable grounds for the suspicion that the police undoubtedly held is to be found in the opinion of Lord Devlin in Hussein –v- Chong Fook Kam [1970] AC 942 at page 948 B:
“Suspicion in its ordinary meaning is a state of conjecture or surmise where proof is lacking; “I suspect but I cannot prove”.  Suspicion arises at or near the starting point of an investigation of which the obtaining of prima facie proof is the end.  When such proof has been obtained, the police case is complete; it is ready for trial and passes on to its next stage.  It is indeed desirable as a general rule that an arrest should not be made until a case is complete.  But if an arrest before that were forbidden, it would seriously hamper the police …. 
Their Lordships have not found any English authority in which reasonable suspicion has been equated with prima facie proof.  In Dumbell –v- Roberts [1944] 1 All ER 326 Scott LJ said at page 329:
“The protection of the public is safeguarded by the requirement …. that the constable shall before arresting satisfy himself that there do in fact exist reasonable grounds for suspicion of guilt.  That requirement is very limited.  The police are not called upon before acting to have anything like a prima facie case for conviction….”
There is another distinction between reasonable suspicion and prima facie proof.  Prima facie proof consists of admissible evidence.  Suspicion can take into account matters that could not be put in evidence at all…… Suspicion can also take into account matters, which, although admissible, could not form part of a prima facie case.  Thus the fact that the accused has given a false alibi does not obviate the need for prima facie proof of his presence at the scene of the crime; it will become of considerable importance in the trial when such proof as there is is being weighed against the alibi.  It would undoubtedly be a very suspicious circumstance.”
21.	Accordingly, he submits that the passage in the judgment of Sir Frederick Lawton in Castorina to which I have already referred, has to be approached with some care.  He points out that this passage in Lord Devlin’s opinion was referred to with approval by Lord Diplock in Holgate - Mohammed –v- Duke [1984] AC 437 at page 443 and by Lord Steyn in O’Hara at page 293.  He submits that there were clearly reasonable grounds for suspecting that one or more of the six who were arrested were responsible for what was, potentially, a serious crime, as well as a breach of trust.  Since all six were of hitherto good character, that fact in itself could not dissipate suspicion.  The police reasonably held the view that the “spot” tape could not be relied upon to determine more accurately the date or time at which the over recording had taken place as it could well have been a copy.  
22.	They took all reasonable steps to reduce the numbers of those who could properly be described as suspects by a careful analysis of the rota, and consideration of the relevant skills of those who were in a position to tamper with the tapes during the relevant time, and had taken steps to narrow the area of suspicion further by inquiries as to whether or not there was a connection between any of the employees and the offender, and by a time consuming analysis of phone calls.  This produced an irreducible minimum of six people.  As a matter of principle, he submits, there is no justification for the argument that there cannot be reasonable grounds for suspecting more than one person of committing an offence, even if it is known that only one person could have committed that offence.  The question is simply whether or not there were reasonable grounds for suspecting that the particular person arrested had committed the offence, however many others may be in the same position.
23.	As to the third Castorina question, he submits that the first submission made by the appellants is quite simply wrong on analysis of the evidence that was given at the trial.  The police officers clearly took into account the appellants’ good character.  As to the second submission, he submits that the judge was fully entitled to come to the conclusion that he did, and that the pleadings adequately covered the finding that he made.  It was a conclusion which justified the police in making the arrests.  In Holgate-Mohammed, Lord Diplock held that an arrest was justified where the police considered that a suspect was more likely to confess to what the officer had reasonable cause to believe to be the truth if that suspect were arrested and taken for questioning to the police station; he said at page 445:
“That arrest for the purpose of using the period of detention to dispel or confirm the reasonable suspicion by questioning the subject or seeking further evidence with his assistance was said by the Royal Commission on Criminal Procedure in England and Wales (1981) (Cmnd. 8092) at paragraph 3.66 “to be well established as one of the primary purposes of detention upon arrest.””

24.	As to the third submission, Mr Freeland points out that this was not a submission made to the trial judge.  He submits that it is misconceived.  The Human Rights Act 1998 is not retrospective and does not apply.  In any event Article 5(1)(c) provides its own complete code for determining whether an arrest is compatible with the Convention.  The protection envisaged is that there should be “reasonable suspicion”, which is the same as the requirement envisaged by the second Castorina question.  The right of liberty expressed by the Article is no more extensive a right than that which has always been recognised in domestic law.  The exercise of discretion has, accordingly, always been scrutinised in the context of that right; and the classic Wednesbury principles are a sufficient and satisfactory control to prevent arbitrary arrest.
25.	In order to resolve the issues raised by these submissions, it is sensible to start by setting out the statutory basis for the power which the police sought to exercise.  Section 24(6) of the Police and Criminal Evidence Act, 1984 provides:
“Where a constable has reasonable grounds for suspecting that an arrestable offence has been committed, he may arrest without a warrant anyone whom he has reasonable grounds for suspecting of being guilty of the offence.”
26.	It is accepted, as I have already indicated, that in determining whether or not the police have acted within the powers conferred by this sub-section, the three Castorina questions modified if necessary by the European Convention on Human Rights are the appropriate questions for the court to determine.  It is also accepted that it is for the police to prove on the balance of probabilities that the arresting officer suspected that the person arrested was guilty of the offence, and that there were reasonable grounds for that suspicion.  It is also accepted that if those two questions are answered affirmatively, the burden is on the arrested person to establish that the discretion was unlawfully exercised.  It is also accepted that the sub-section required the court to consider the state of mind of the arresting officer, or officers and not that of any other officer, save in so far as that other officer may have given information to the arresting officer which could provide the arresting officer with reasonable grounds for his or her suspicion.  It follows that, in the present case, it is primarily the evidence of Police Constable Ward which is relevant save to the extent that it is clear that things said to her by Detective Sergeant Richards could properly provide reasonable grounds for her suspicion and a proper basis for the exercise of the power of arrest.  PC Abdullah although involved in the arrests, was not available to give evidence.  
27.	In order to evaluate the appellants’ criticisms of the judge’s judgment, it is, I think, necessary to refer to the respondent’s defence, and to some passages in the evidence of Police Constable Ward and Detective Sergeant Richards.  The relevant paragraph in the defence was in the following terms:
“9.  Before any arrests were made Detective Sergeant Richards, a very experienced officer, carefully reviewed the circumstances and discussed the matter with colleagues.  In particular he took into account:
(1)  That the CCTV room is a sensitive operation which on occasions provides vital information in relation to serious arrestable offences and therefore the integrity of the same is very important.
(2)	There were strong reasons for believing that the taping over of the recording of the original incident had been done deliberately, and that, if this was the case, the same would, on the face of it, have been a serious and deliberate attempt to pervert the course of justice and would also have been a breach of trust.
(3)	Mr Marriott had informed the police that there were always two employees in the relevant control room and thus it seemed unlikely the tapes could have been accidentally interfered with by one employee without the knowledge of at least one other.
(4)	That all reasonable efforts had been made to resolve this matter without recourse to effecting arrests, even to the extent of offering the person or persons involved the opportunity to come forward to be dealt with solely by way of internal discipline if it were the case that the erasure had occurred accidentally but that these efforts had failed to identify who was responsible.
(5) 	That efforts to narrow down the number of suspects had been made, and whilst further forensic tests were contemplated these were likely to take a considerable time and were not guaranteed to be positive or of assistance to the investigation.
(6)	That a failure to identify the person who had erased the tape would mean that suspicion would remain over all six individuals, some of whom were entirely innocent, and/or could lead to a recurrence with more serious consequences.
(7)	That using the option of voluntary attendance would, or could, involve further delays in the investigation and if more than one person was involved this would give them the opportunity to collude in the stories and was unlikely to prove effective given the failure of the person involved to come forward voluntarily previously”
28.	In his statement, Detective Sergeant Richards after having set out the material facts to which I have already referred and those which were set out in the defence, continued:
“10.  …. I had to decide whether I thought there were reasonable grounds for suspicion that an arrestable offence had taken place.  I decided that there were reasonable grounds after discussions with my colleagues.
11.	The option of voluntary attendance was considered.  This would avoid the necessity of having to arrest the six individuals.  In discussion with my colleagues it was decided that this would not be a suitable option.  At that time the likelihood of a positive result from the forensic test was unlikely, and furthermore, we were experiencing serious but unavoidable delay.  I feared, particularly if there had been a conspiracy between two or more of the individuals under suspicion, that the initiative would be lost.  Furthermore voluntary attendance was likely to cause considerable delay in investigation and therefore I believed it was prudent to arrest and interview all six parties at the same time.”
29.	In his evidence in chief he accepted that the decision to arrest was ultimately his.  He described why it was that the police doubted that the “spot” tape was the original tape, and why he was unable to get any assistance from the experts whom he had approached.  He further explained why it was he decided against asking the suspects to come for interview voluntarily, essentially repeating what was in his statement and in the defence.  
30.	In cross-examination he explained how it was that he believed that Mr Marriott had spoken to the staff and given them the opportunity to give their account without any practical result.  He explained why he did not obtain the information that was subsequently obtained when it was accepted that the “spot” tape was the original.  When it was put to him that the interviews were such that the questions could readily have been put to the appellants without the necessity for their arrest he said:
“Bearing in mind that each of the persons had been given the opportunity to come forward, I was firmly of the opinion that had we arrested – had we spoken to them either at their homes, at work, or even as voluntary attendees, we might not necessarily have got to some of the facts as produced by – by Mrs Jukes, Starbuck was at the machine in the afternoon.  I know she said that she would have said that but I had no guarantee – I didn’t know these people – I don’t know who they are or what they are.”

31.	When it was put to him that he knew full well the nature of the appellants, in that they were long serving members of the CCTV Unit and were all of good character he said:
“Well, yes, that is all well and good but it is only information which was on the computer.  I do not know these people.  I – they may be the most wonderful people in the world.  I don’t, I really don’t know.  On the other hand they might be very evil but had never been caught for anything.”
32.	In her statement, Police Constable Ward said:
“All of our inquiries were considered before the decision was made by Sergeant Richards as to whom we had reasonable grounds to suspect for the offence and for arrest.  Predominantly we took into account the discussions that we had with Paul Marriott with regard to duty rosters and location of operatives that were on duty.  As a result we decided to arrest Alan Starbuck, Kathleen Cumming, Bryan Fox, David Worthy, Linda Jukes and John Stokoe.
A briefing then took place between myself and DS Richards and DC Abdullah.  We considered that as the staff had had the opportunity to come forward and volunteer information but had not done so, then requesting their voluntary attendance at the police station was unlikely to be effective.  We considered that we had reason to believe that one of the six persons had tampered with the evidence and one had seen it being done.  It was felt that the best course of action was arrest the six and to interview them under caution.  However we decided to take a gentler approach and to interview the six persons regarding their role in the organisation and who had been on duty with them, to encourage them to come forward with information if they thought that a genuine mistake had been made with the tape and to emphasise the importance of the problem if they had seen the tampering going on but didn’t want to accuse a friend.”
33.	In cross-examination she repeatedly made the point that the fact that they had doubts as to whether the “spot” tape was original meant that they were uncertain as to when the tapes had been tampered with.  It followed, she said, that all six who were arrested were suspects.  She said:
“I suspected that some one had done it.”
34.	She then explained what she meant:
“It was reasonable to believe that either he or the others that were identified had altered these tapes.”
35.	She accepted that all those arrested were of good character and had worked closely with the police.  She said that she and Detective Sergeant Richards had considered whether or not to ask all those arrested to the police station to answer questions voluntarily.  The questions and answers thereafter were as follows:
“Q.	And what was the disadvantage in that course? –
A.	It was believed that seeing as these people had the opportunity to come forward and offer any information and that hadn’t been done and – as you have pointed out, it is a serious offence, had these people at any point decided not to speak to us they would have got up and walked out of a police station and we would have then ended up arresting them to continue with the questioning so it was deemed that we exercise our power of arrest.
Q.	So you seriously thought, did you, that they may not cooperate with the police, these five of good character who spent many years working with the police?  You seriously thought that did you? –
A. 	Yes
Q.	You sure about that? –
A.	I am positive about that sir.”
36.	In the light of that evidence, the judge was entitled to conclude that the police officers genuinely suspected that one or more of the six that they had arrested had committed the offence of perverting the course of justice.  And there has been no challenge to that finding.  It is also clear that the judge was entitled, on this evidence, to accept that the police had genuine doubts about whether the “spot” tape was the original and accordingly had not at the time of the arrests been able to pin point the time at which the “spot” tape had been recorded over.  The police had made efforts to try to find a connection between the youth who had been arrested and any of those working in the Warden Services Department, but had been unable to discover any such connection.  They had spent much time analysing telephone calls to see whether that provided them with any leads.  They had been able to reduce the number of staff who had the opportunity to either tamper with the tapes, or witness the tampering of the tapes to the six who were arrested.  The police had explained to the judge how it was that they were unable to obtain any assistance from forensic scientists.  The judge clearly accepted, and it seems to me that again he was entitled to do so on the evidence, that the police had taken all reasonable steps and were left with the fact that one or more of the six who were arrested must have been the culprit.  The question therefore is whether or not that situation can amount in law to “reasonable grounds” for the suspicion that they undoubtedly had.
37.	I have no doubt that this phrase does require the court to determine whether or not the police had facts or information to support the police officers’ suspicion as Sir Frederick Lawton said in Castorina and The European Court of Human Rights considered to be the necessary protection from arbitrary arrest in Fox Campbell & Hartley.  Indeed in that case the United Kingdom Government accepted that Article 5.1(c) required the existence of facts or information which would satisfy an objective observer that the person concerned may have committed the offence.  I do not consider that, properly understood, there is any conflict between what Lord Devlin said in Hussein and what Sir Frederick Lawton said in Castorina.  That is why both passages were cited with apparent approval in O’Hara.  The passages from Hussein which have been cited both to us and by Lord Steyn were concerned with the question whether or not the Federal Court of Malaysia had applied the right test to determining whether the police had made an arrest on reasonable suspicion of an offence having been committed.  Siphon FJ, who delivered the judgment of the court, said that the information available to the police “was insufficient to prove prima facie a case against the plaintiffs” of any offence.  It follows that the Privy Council was concerned as to whether or not reasonable suspicion was to be equated to a prima facie face.  It was in that context that Lord Devlin was seeking to identify the nature of a suspicion and whether it had to be based upon admissible facts sufficient to establish a prima facie case.
38.	It is instructive to look to the way in which the Privy Council dealt with the facts of the case.  As a car passed a lorry carrying logs, which was coming in the opposite direction, a log fell off the lorry and smashed into the windscreen of the car killing one of its occupants.  The next morning, the lorry was found by the police; and the two men who had been in the lorry were arrested.  The police at that stage did not know which of the two had been driving.  It was accepted that the police had good grounds for suspecting that this was the lorry which had in fact had been involved in the incident.  When questioned, the two who had been arrested denied that they had been at the scene.  They gave an alibi which, when checked, could not be corroborated.  The Privy Council concluded that when the police made their arrest, they only had a suspicion that one of the two had been the driver; but they did not have sufficient information to suspect that the incident had been the result of an offence such as reckless driving.  The fact that the lorry had not stopped was not in itself enough.  Lord Devlin expressed the conclusions of the Privy Council as follows at page 499:
“The police, who had admittedly good grounds for suspecting that it was the plaintiffs’ lorry which was in fact involved, must be credited with equally good grounds for suspecting that the alibi was false.  When checked, no corroboration was found for it.  These facts, added to the failure to stop, were enough in their Lordships opinion to raise at this later stage a reasonable suspicion that the plaintiffs were concerned in a piece of reckless driving.  But the case falls far short of prima facie proof.”
39.	The result was that the plaintiffs were entitled to damages for unlawful arrest and false imprisonment up to the time when they gave the alibis which the police could reasonable conclude were false.
40.	It can be seen, therefore, that there is nothing in what Lord Devlin said in Hussein which in any way conflicts with the statement of principle by Sir Frederick Lawton in Castorina.   The only caveat is that the word “facts” must not be given a restrictive meaning.  It clearly includes information, as was the view of the European Court of Human Rights in Fox, Campbell and Hartley; and information can be information obtained from a third party, such as a senior officer, as in the case of O’Hara.   The decision in Hussein is also instructive in that the Privy Council clearly took the view that the police were entitled to arrest both, even though only one of them could have been the driver.
41.	In my view, there is nothing in principle which prevents opportunity from amounting to reasonable grounds for suspicion.  Indeed in some circumstances opportunity may be sufficient to found a conviction.  That would be the case where the prosecution can prove that no one else had the opportunity to commit the offence.  The question in the present case is whether opportunity is sufficient to be reasonable grounds for suspecting six people when the likelihood is that it was only one or perhaps two of those six who were responsible. Again there can be nothing in principle wrong with arresting more than one person even if the crime can only have been committed by one person: see Hussein.  Where a small number of people can be clearly identified as the only ones capable of having committed the offence, I see no reason why that cannot afford reasonable grounds for suspecting each of them of having committed that offence, in the absence of any information which could or should enable the police to reduce the number further.  In this case, the only information short of interviewing the appellants and Mr Starbuck, which could have achieved that was the information enabling the police to determine the time at which the over-taping of the “spot” tape or the tampering with the “multiplex” tape had taken place.  The judge concluded, and in my view he was entitled to, that the police were justified in doubting whether the “spot” tape was genuine.  There was never any suggestion that the police could or should have been able to identify when the “multiplex” tape had been tampered with.  In these circumstances, the judge could properly find, as he did, that there were reasonable grounds for suspecting all six of those arrested of having committed the offence. 
42.	Turning to the third Castorina question, the passages in the evidence to which I have referred make it abundantly clear that both Detective Sergeant Richards and Police Constable Ward were well aware at all times that the appellants and Mr Starbuck were of good character and had worked closely with the police.  Detective Sergeant Richards’ answers in this respect may appear to some somewhat cynical, but to others they may reflect healthy scepticism.  The fact is that one or more people of good character had apparently deliberately interfered with the tapes.  The question is whether given that that was the situation, the police officers could properly come to the conclusion that nonetheless they should exercise the power of arrest.  Clearly the reason for deciding to arrest as opposed to asking the suspects to come to the police station voluntarily was the critical question.  It clearly troubled the judge.  His conclusion that the police wanted to assert maximum pressure to get the confession that had eluded management was in my view fully justified.  Although it was never expressed in precisely these terms, it seems to me to be implicit in the pleaded justification in paragraph 9(7) of the defence, and, as the judge had said, implicit in the evidence of Detective Sergeant Richards and indeed Police Constable Ward.  That is a perfectly proper purpose, as Lord Diplock said in Holgate-Mohammad .
43.	But that does not, of itself, answer the third Castorina question.  The mere fact that they had reasonable grounds for the arrest, and proposed to arrest for a proper purpose still leaves the question of whether or not it was a proper exercise of discretion.  In determining this question it seems to me that it is necessary to bear in mind that the right to liberty under Article 5 was engaged and that any decision to arrest had to take into account the importance of this right even though the Human Rights Act was not in force at the time.  To that extent I accept the appellants’ submissions.  The court must consider with care whether or not the decision to arrest was one which no police officer, applying his mind to the matter could reasonable take bearing in mind the effect on the appellants’ right to liberty.  There is no doubt that when the appellants and Mr Starbuck were arrested and taken to the police station, the interviews were conducted more in the form of questions designed to elicit information, than an interrogation.  But that does not seem to me to undermine the judges’ conclusion that the arrest was intended to bring pressure to bear on the appellants and Mr Starbuck.  Arrest undoubtedly did.  The way that the interviews were conducted reflected the fact that the police knew full well that they were dealing with people of hitherto impeccable character, and were accordingly anxious not to behave any more oppressively than they had by arresting them.  I do not think the form of questioning in any way undermines the judges’ conclusion that was the reason for arrest.
44.	However the judge seems to me to have been right to conclude that with hindsight this was not necessarily the right decision.  The chances are that the police would have obtained exactly the same information from the appellants and Mr Starbuck had they interviewed them voluntarily.  What cracked the case was the conclusion that they could and should rely on the genuineness of the “spot” tape.  But as the judge said, that was hindsight.  Having found that the police were entitled to doubt its genuineness, the judge was, in my view, also entitled to conclude that because there appeared to have been such a serious breach of the security of the CCTV monitoring system, the police could reasonably take the view that the matter needed to be brought to a head speedily and that the appellants had not satisfied him that the decision to arrest was outside the boundaries of discretion which the police had to exercise.  Although he did not, because it was never submitted to him that he should, approach the matter having regard to the provisions of Article 5 of the Convention, the appellants have not persuaded me that his decision was wrong.  The judge was obviously keenly aware of the fact that the appellants right to liberty had been infringed and considered the case in that light.  It has to be remembered that the protection provided by Article 5 is against arbitrary arrest.  The European Court of Human Rights in Fox, Campbell and Hartley held that the protection required by the article was met by the requirement that there be “reasonable grounds” for the arrest.  I do not therefore consider that Article 5 required the court to evaluate the exercise of discretion in any different way from the exercise of any other executive discretion, although it must do so, as I have said, in the light of the important right to liberty which was at stake.
45.	I would therefore dismiss this appeal.

Lord Justice Brooke:
46.	I was very uneasy about this case throughout the hearing of the appeal.  I remain very uneasy about it.  It seemed very strange that the law could raise no protest when five loyal employees of the council could be arrested and detained in their local police station for varying lengths of time – one of them was locked up in a police cell for four and a half hours and another for nearly seven hours – when nobody had previously made any attempt to interview them.
47.	It appears to me that in this context the following findings of fact by the judge were of paramount importance:
(i)	At a meeting between police and management on 27th May the police were told that the relevant members of staff would be interviewed individually;

(ii)	Mr Marriott, the manager of the Central Control unit, thereafter failed to carry out any or any proper enquiry or interviews with the relevant staff, in dereliction of his duties as a manager;

(iii)	The police believed that a proper investigation had taken place and had yielded no information.
48.	These findings of fact were not challenged on the appeal.  What the likely outcome would have been if they had been challenged is not for me to say.  But given these unchallenged findings of fact I find it impossible to disagree with the disposal of this appeal, since I agree with Latham LJ’s analysis of the law to be applied.
The President:    
49.	I agree that the appeal be dismissed
Order:	Appeal dismissed.  Application for permission to appeal to the House of Lords refused.
(Order does not form part of the approved judgment)