England and Wales High Court (Administrative Court) Decisions

IN THE HIGH COURT OF JUSTICE
QUEEN'S BENCH DIVISION
DIVISIONAL COURT

		Manchester Civil Justice Centre 1 Bridge Street, West Manchester, M60 9DJ
		21/08/2015

Lord Justice Treacy :

Introduction

1. This is an appeal by way of Case Stated against the decision of District Judge Clarke in the Manchester and Salford City Magistrates Court on 23 September 2014 to convict the appellant of obstructing a police officer in the execution of her duty contrary to section 89(2) of the Police Act 1996. The appellant received an absolute discharge with no order as to costs.
2. The Case Stated is as follows:

In the High Court of Justice

Queen's Bench Division

Between

Kate McCann

and

The Crown Prosecution Service

Case stated by James Clarke District Judge (Magistrates' Court) acting in and for the Local Justice Area of Greater Manchester in respect of his adjudication as a Magistrates' Court sitting at Manchester and Salford.

CASE

1. On the ….… day of …………..… 2015, an information was preferred by the respondent against the appellant that the appellant had on 6^th February 2014 wilfully obstructed Inspector Chatterton a constable acting in the execution of her duty contrary to sec 89(2) Police Act 1996

2. I heard the said information on the 23^rd day of September 2014 and found the following facts:

a. The charge arose from the appellant's presence on 6^th February 2014 on Barton Moss Road, Greater Manchester; an access road to a site where test drilling commonly known as "fracking" was being carried out.

b. The appellant had, together with another man Tricky of the Clan Cairns (who does not appeal the conviction) and Ms Tammy Samede and Mr James Alden (both of whom initially did join this appeal but who have since withdrawn) attended with others at the road in order to protest at what they believe to be environmental damage consequential to the drilling.

c. The appellant, Ms Samede, Mr Alden and Tricky of the Clan Cairns had placed themselves in the middle of the access road, were seated and had locked themselves together by the arms, using a combination of chains, locks and drainpipes in a practise known as a "lock on". Other protesters fed them in an apparent picnic.

d. A number of lorries heading for the drilling site were unable to pass because of the obstruction to the route.

e. Inspector Chatterton of Greater Manchester Police was the officer on site in charge of public order. At a morning briefing by senior officers, she had been misinformed about the classification of the road but acted upon what she believed to be the case: that Barton Moss Road was a public highway.

f. She instructed the appellant and others to move on the basis that they were obstructing a public highway, an offence contrary to section 137 Highways Act 1980.

g. The group refused to move. The appellant's refusal was based upon a belief (as it happens correct) that the passageway was a private road with a public footpath. The appellant and others stated this to the officers at the time.

h. The Inspector did not become involved in discussions about the protestors' claims that the road was a private one. I accepted her evidence that she had been fully briefed on the location at the start of the day and told that it was a public highway. By the manner in which the protestors were disputing the classification of the road (shouting, cheering, waving placards and laughing) she did not consider it to be reasonable to accept this as a clear statement of law (her words). Further, there was a supervising Bronze Commander at the scene as a tactical adviser and who would have been aware of the statements about the road. As such, the inspector would have expected any change in her orders to come from him.

i. The appellant and others refused to move and were arrested as a consequence. Kate McCann was initially arrested for the section 137 Highways Act 1980 offence but shortly afterwards for obstruction contrary to section 89(2) Police Act 1996. Only the Police Act charge was pursued at trial.

j. The classification of the road as public or private had been the subject of significant dispute before and after the events of 6^th February 2014. Due to a large number of related prosecutions in which the issue was raised, the Crown Prosecution Service had taken counsel's advice on the point. At trial, a formal admission was made by the prosecution that the access road was a private road with a public footpath and therefore not a road to which the Highways Act 1980 applied. Vehicular access required permission of the landowner.

k. In a dramatic turn of events during the trial, it became clear that Inspector Chatterton had not been told that, since 6^th February 2014, the road had been confirmed to be a private road. Nevertheless, her evidence was that had she been aware it was a private road, she "would have used different powers" to require the appellant and others to move and stop obstructing the route. I accepted this as a truthful statement by the officer, made spontaneously at a point she was confronted with this new information about the status of the road.

l. Inspector Chatterton was not asked to specify what powers she would have used. She made no reference to sec 68 Criminal Justice & Public Order Act 1994 at this point in her evidence or when relating her discussions with the appellant and others. She did state that she was aware that the lorry drivers had permission from the landowner to drive along the path and pass stating that this was a lawful activity. She therefore demonstrated knowledge of at least some elements of the provision upon which the prosecution were relying namely section 68 Criminal Justice and Public Order Act 1994. She said would have done the same thing, that is instructed the protestors to move, had she been aware of the correct classification of the route as a private road.

3. It was contended by the appellant that:

Inspector Chatterton was wrong in law in her belief that the protestors were committing an offence under the Highways Act 1980.

She had no power to require the appellant to move to prevent obstruction of a public highway because it was not a public highway.

This rendered the officer's request outside her powers and she was not therefore acting in the execution of her duty.

Any actions by the appellant to frustrate the officer's aim could not therefore be obstructing the execution of her duty.

It was wrong for the respondent to contend that the inspector had that power to prevent an offence contrary to section 68 Criminal Justice and Public Order Act 1994 because it had not been proven that such an offence had been committed

A submission was made on behalf of a co-defendant that the fact that the officer was acting in good faith or that her error was reasonable did not mean she made a lawful request. The appellant, though his advocate Miss Andrews, adopted that submission in full but made no further comment on the question of reasonableness.

4. It was contended by the respondent that:

Inspector Chatterton had a lawful right to ask the defendants in this case to stop causing an obstruction.

She acted at all times in good faith.

The fact that she thought the power was under the Highways Act 1980 as opposed to the Criminal Justice and Public Order Act 1994 was a mistake of fact not law.

The error did not place the officer outside the execution of her duty because there was a corresponding power under the 1994 Act.

The appellant had by his behaviour wilfully obstructed the officer by refusing to move and frustrating her efforts to prevent a continuation of the aggravated trespass offence.

5. I was referred to the following cases

Tynan v Balmer (1967) 1QBD 91

Rice v Connolly (1966) 2 QB 414

Cumberbatch v Crown Prosecution Service: Ali v Department of Public Prosecutions [2009] EWHC 3353 (Admin)

Fitzpatrick v Metropolitan Police Commissioner

Christie v Leachinsky [1947] AC 573

Elkington v Director of Public Prosecutions [2012] EWHC 3398 (Admin)

6. I was of the opinion that:

a. The actions of the appellants were wilful and intentional. Their presence at the scene may have been to raise awareness about and protest about the drilling, but their actions in locking themselves together and refusing to move had been intended to obstruct the police officers by making it more difficult to remove them.

b. Inspector Chatterton made a mistake of fact about the status of the road and therefore the offence she believed was being committed.

c. The issue over the road being public or private had in fact itself been the subject of considered advice. This was referred to within the prosecution skeleton argument. It had not, apparently, been a simple question to resolve.

d. Section 68 Criminal Justice and Public Order Act 1994 could well have applied to the situation but I did not have to be satisfied that an offence under that section had in fact been committed, merely that the officer had reasonable grounds to suspect an offence was being committed.

e. The mischief that the officer was addressing was the obstruction of the route to lorries. She was aware that other powers could be available to her and her attempts to prevent a continuing offence meant she was acting in the execution of her duty.

f. The Appellant's actions did obstruct the police duties as it caused a backlog of traffic on the route, potentially amounting to an offence under the 1994 Act and which the officers were seeking to prevent.

g. The Officer's belief, albeit mistaken, was reasonable in the circumstances prevailing at the time and whilst I did not specifically address the reasonableness of the mistake, I did address my mind and my judgement to the reasonableness of the officer's suspicion that an offence was being committed. I reasoned that it mattered not that the officer had the wrong offence in mind because her action was in response to the same activity by the defendants and same mischief that she was seeking to prevent.

h. In relation to the case law provided, the appellant's case fell somewhere between Tynan (in which it was proven that an offence other than the one the officer had in mind had in fact been committed) and Cumberbatch (wherein it was conceded that no offence had been committed and the subsequent arrest was unlawful) because an offence under section 68 had neither been proven nor disproven on the evidence I had heard. There was no question of Inspector Chatterton deliberately acting on a false premise as in Christie v Leachinsky.

i. The officer had reasonable grounds to suspect an offence was being committed and even though she had the wrong one in mind (section 137 Highways Act 1980), the facts could have lent themselves to another offence (section 68 aggravated trespass) and so she was therefore acting in the execution of her duty.

and accordingly I convicted Kate McCann of wilfully obstructing Inspector Chatterton a constable acting in the execution of her duty on 6^th February 2014 contrary to section 89(2) Police Act 1996

The appellant had no previous criminal convictions, no means and did not claim state benefits. I accepted that there was a genuine belief in the cause for which the group including the appellant was demonstrating. Whilst not condoning the cause, I nevertheless acknowledged that there had been an honest motive for the protest. More to the point, I accepted that there had a genuine belief by all of the defendants mentioned that they were not required to move away from the road because they believed they were not committing the offence of obstructing a public highway that the officer had warned about. The appellant had been correct in this assertion about the classification of the road. I made an absolute discharge.

QUESTIONS

7. The questions for the opinion of the High Court are:

a. Was the officer's mistake about the classification of the road an error of law or fact?

b. Was the officer's mistake about the power she was exercising an error of law or fact?

c. Did either mistake, reasonable or not, place her outside the execution of her duty?

d. Can an officer still have reasonable grounds to suspect an offence even if acting upon a mistaken belief? Specifically, in the circumstances of this case, was Inspector Chatterton's mistake reasonable? Did she have reasonable grounds to suspect an offence under Highways Act 1980 had been committed?

e. Is it necessary for the offence the officer suspects (be that obstruction under the Highways Act 1980 or aggravated trespass under section 68 Criminal Justice & Public Order Act 1994) to be proven to the criminal standard for the officer to be acting in the execution of her duty (and therefore capable of being obstructed in its execution), or are reasonable grounds to suspect sufficient?

f. Does it matter that the officer had the wrong offence in mind?

g. Was I entitled, as the prosecution submitted, to look at the others powers available to the officer that could have applied to the correct facts?

h. Does the answer to question g depend upon whether the officer herself was aware of those powers?

Dated this 4^th day of February 2015

James Clarke

District Judge (Magistrates' Court)

The Appellant's Case

3. Although a large number of questions have been posed by the Case Stated, Mr Brigden for the appellant based this appeal on two grounds only:

i) whether the mistake of fact regarding the classification of Barton Moss Road made by the officer was unreasonable so as to place her outside the execution of her duty; and

ii) whether in the circumstances the officer could not be within the execution of her duty on the basis that another offence, namely aggravated trespass, may have been committed.

4. The appellant contended that the officer's genuine mistake regarding the status of the road was not reasonable. The appellant and her companions had asserted correctly that the road was not a highway, and since they were ultimately shown to have been correct, the police should have done more to ascertain the correct position before acting on an erroneous basis. This was particularly so when there was no urgency in the situation, for example, by way of a threat of public disorder.
5. Mr Brigden drew attention to the decision of the European Court of Human Rights in Fox, Campbell and Hartley v The United Kingdom (Application No 12244/86:12245/86:12283/86), BAILII:[1990] ECHR 18 at paragraph 32 where the Court stated:

"The "reasonableness" of the suspicion on which an arrest must be based forms an essential part of the safeguard again 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 on all the circumstances."

6. Counsel also drew attention to the Police and Criminal Evidence Act Code G (2012 revision) which states at Note 2 that:

"Facts and information relevant to a person's suspected involvement in an offence should not be confined to those which tend to indicate the person has committed or attempted to commit the offence. Before making a decision to arrest a constable should take account of any facts and information that are available, including claims of innocence made by the person which might dispel the suspicion."

7. In further support of the argument that the officer could not reasonably have suspected a breach of the Highways Act, Mr Brigden referred to paragraph 2L of the Case where the judge had found that the officer had stated that she was aware that lorry drivers had permission from the landowner to drive along the path. It was argued that such a statement was inconsistent with the road in question being a public highway to which section 137 of the Highways Act 1980 applied. It was consistent with Barton Moss Road being a private road. Accordingly this finding demonstrated that the officer's mistake about the status of the road was unreasonable so that when the officer arrested the appellant for obstructing the highway, and expressly stated that she was doing so, she could not have been acting in the execution of her duty.
8. Section 137 of the Highways Act 1980 provides:

"If a person, without lawful authority or excuse, in any way wilfully obstructs the free passage along a highway he is guilty of an offence and liable to a fine not exceeding level 3."

9. The offence of aggravated trespass was created by section 68 of the Criminal Justice and Public Order Act 1994 which provides:

"(1) A person commits the offence of aggravated trespass if he trespasses on land and, in relation to any lawful activity which persons are engaging in or are about to engage in on that or adjoining land, does anything there which is intended by him to have the effect –

(a) of intimidating those persons or any of them so as to deter them or any of them from engaging in that activity;

(b) of obstructing that activity; or

(c) of disrupting that activity."

10. In relation to this section Mr Brigden argued that it would be wrong for the respondent to rely on section 68 when the officer did not mention it and when it had not been in the officer's mind. Moreover there was no prima facie case to show that the appellant was a trespasser on the land in question. Further, a section 68 offence should be regarded as logically inconsistent with a section 137 offence and, being so dissimilar, should not enable a finding that the officer was acting in the execution of her duty.

The Respondent's Case

11. On behalf of the respondent Mr Ratliff pointed out that there was no dispute that the appellant had obstructed the officer by refusing to comply with the direction to remove herself from the road. The essential question was whether in giving the direction to the appellant to move the officer was acting in the execution of her duty. He submitted that that question could be subdivided into three issues:

i) Was the direction to the appellant that she should move from the road lawful in that it was done in the discharge of the officer's duties?

ii) Was there an obligation to explain to the appellant why she was being told to move from the road?

iii) If there was no such obligation did the fact that the police gave the appellant an erroneous reason mean that the officer ceased to be acting in the discharge of her duty?

12. Accordingly Mr Ratliff submitted that the focus of the appellant's argument, with its concentration on the reasonableness of the mistake made by the officer and on powers of arrest, was misplaced.
13. Mr Ratliff relied on a passage of a judgment of Lord Parker CJ in Rice v Connolly [1966] 3 WLR 17 at page 21A-C:

"What the prosecution have to prove is that there was an obstructing of a constable; that the constable was at the time acting in the execution of his duty and that the person obstructing did so wilfully. To carry the matter a little further, it is in my view clear that "obstruct" under section 51(3) of the Police Act 1964, [a precursor of section 89(2) of the Police Act 1996], is the doing of any act which makes it more difficult for the police to carry out their duty. That description of obstructing I take from Hinchcliffe v Sheldon [1955] 1 WLR 1207. It is also in my judgment clear that it is part of the obligations and duties of a police constable to take all steps which appear to him necessary for keeping the peace, for preventing crime or for protecting property from criminal injury. There is no exhaustive definition of the powers and obligations of the police, but they are at least those and they would further include the duty to detect crime and bring an offender to justice."

14. Mr Ratliff accepted that in modern times the passage cited from Lord Parker's judgment should be read as if it stated:

"It is part of the obligations and duties of a police constable to take all steps which reasonably appear to him to be necessary…for preventing crime…"

15. That concession appears to us to be well-founded as otherwise the officer would have an unfettered discretion as to how to act. Mr Ratliff urged that the officer in giving a direction to the appellant to move in the belief that the appellant was obstructing lawful passage along the highway was taking steps which reasonably appeared to her to be necessary for preventing crime. Accordingly what she did was lawful, and it was a direction in the execution of her duty. The fact that she had formed the view that the obstruction was taking place on public land rather than private land did not affect the position. In addition the fact that the officer had given the wrong reason for her direction did not mean that the officer was no longer acting in the execution of her duty.
16. In contrast to the position at common law established in Christie v Leachinsky [1947] AC 573 at page 587 where Viscount Simon held that there was no requirement to give reasons for an arrest where the person being arrested knows the general nature of the alleged offence for which he is detained, section 28 of the Police and Criminal Evidence Act 1984 requires that a person arrested is informed of the ground for arrest at the time of or as soon as practicable after the arrest unless this was not reasonably practicable because that person escaped while being put under arrest. This is so whether or not the reasons are clear to the person arrested. That statutory change to the position at common law relates only to arrest and arises out of the need for there to be an explanation to the person being detained of the reason why he or she is being deprived of his liberty. That provision does not affect the common law where a police officer is taking some step short of detention, such as giving a direction to move with a view to preventing crime.
17. Alternatively, if at common law there was a requirement to give reasons for an arrest, for example where the reason for arrest is not apparent to the person being arrested, this burden is relatively light. Viscount Simon at page 587 stated that the requirement does not mean that technical or precise language need be used. The requirement is that a person knows in substance why he is being detained. Lord Simonds at page 593 said that it was not an essential condition of lawful arrest that the constable should at the time of arrest formulate any charge at all. The arrested man was entitled to be told what was the act for which he was being arrested. This can be transposed to the situation where a police officer is not arresting, but is giving a direction.
18. Accordingly in this case where it was clear to the appellant that she was being asked to move because she was blocking the road the officer was not obliged to give reasons for the direction and it would be remarkable if by giving the incorrect extra detail relating to the statute the officer thereby ceased to be in the execution of her duty. In the circumstances the elements of the offence were made out since in directing the appellant to move from the road the officer was acting in the lawful discharge of her duties in circumstances where she was under no obligation to give reasons for the direction. The fact that the reasons given were erroneous did not take the officer outside the scope of her duties. The appeal should be dismissed.

Discussion

19. It seems to me that the key question in this appeal is whether or not Inspector Chatterton was acting in the execution of her duty. There is no issue before us as to whether what the appellant did amounted to obstruction. I consider that what needs to be examined is the actions and intentions of the officer actually involved with the appellant rather than the position of police officers generally. For this reason I consider that the judge was right not to investigate whether the mistake made by other officers who briefed Inspector Chatterton as to the status of the road was one which was reasonably made. The focus of the judge's findings was properly on Inspector Chatterton's state of mind. In that respect there is a specific finding that her belief as to the status of the road as a highway was reasonable and a further finding that she had reasonable grounds to suspect that an offence (albeit the wrong one) was being committed.
20. In holding that the District Judge was correct in examining the position of Inspector Chatterton rather than others who had briefed her I have considered O'Hara v Chief Constable of R.U.C. [1997] 2 WLR 1 in which it was held that the test to determine whether reasonable grounds for suspicion to justify arrest existed was partly subjective and partly objective. The arresting officer must have formed a genuine suspicion that the person being arrested had been concerned in offending and there had to be reasonable grounds for forming such a suspicion. Such grounds did not have to be based on the officer's own observations but could arise from information he had received even if it was subsequently shown to be false, provided that a reasonable man, having regard to all the surrounding circumstances, would regard them as reasonable grounds for suspicion.
21. In Clarke v Chief Constable of North Wales Police [2000] All ER (D) 477 this court held that although the power of arrest without warrant depends on the existence in the mind of the arresting officer of reasonable suspicion of the material elements of an arrestable offence, there is no requirement of law that the constable must have first hand knowledge of these. So long as they come from a source which is reasonable for her to rely on they can properly form the basis of a reasonable suspicion in the constable's own mind. This approach was followed in Alford v Chief Constable of Cambridgeshire [2009] EWCA Civ 100 where this court held that the arresting officer could rely on a briefing from another police officer as a basis for having reasonable grounds for suspicion.
22. More recently in R (Rawlinson and Hunter Trustees) v Central Criminal Court [2013] 1 WLR 1634 Sir John Thomas (as he then was) rejected a submission that the O'Hara principle should not apply in circumstances where a constable relies on information provided by another member of the investigation team where that information was misleading and the other team member knew or ought to have known it was misleading.
23. It thus seems to me that the appellant's primary attack upon the reasonableness of the officer's mistake regarding the status of the road is misconceived. Insofar as the submission was based on the assertion that those who had briefed Inspector Chatterton must have been at fault in failing properly to ascertain the status of the road, that is not a consideration which should impact upon Inspector Chatterton as the officer who gave the instruction to the appellant to move in the genuine belief that the information provided was correct. It is clear from the judge's findings that he accepted the officer's reliance on the information provided to her was genuine and reasonable. The judge then went on to consider the particular circumstances relating to her, namely the assertions by the appellant and others that the road was a private road. That fact did not deflect the judge from concluding that the inspector reasonably believed that an offence was being committed, and in my judgment he was properly entitled to come to that conclusion.
24. I have already indicated my agreement with the acceptance by counsel for the respondent that the word "reasonably" should be interpolated into the description of a constable's duties given by Lord Parker in Rice v Connolly, so that an officer's duty can be delineated in the present context as the obligation to take all steps which reasonably appear to that officer to be necessary to prevent crime (amongst other things). Whilst this introduces some level of objectivity in assessing the officer's actions it seems clear to me that the judge's findings mean that this element was satisfied. The judge made those findings notwithstanding his recording of the fact that the appellant and others had protested that they were not in fact on a public highway. Having recorded the fact of the protestors' claims about the status of the road the judge appears to have accepted the genuineness of the Inspector's evidence as to her reaction to that, (see paragraphs 2G and 2H of the Case), and went on to hold at paragraph 6G and 6I that the officer's belief as to the status of the road was reasonable in the circumstances prevailing at the time and that she had reasonable grounds to suspect that an offence was being committed. As there was a proper basis for this then it seems to me that the officer would have lawfully been carrying out her duties in the way indicated in Rice v Connolly.
25. The scope of a constable's duty was also considered in R v Waterfield and Lynn [1963] 48 Cr App R 42 where at page 47 Ashworth J said:

"In the judgment of this court it would be difficult…to reduce within specific limits the general terms in which the duties of police constables have been expressed. In most cases it is probably more convenient to consider what the police constable was actually doing and in particular whether such conduct was prima facie an unlawful interference with a person's liberty or property."

26. In order for the offence of obstruction to be committed, therefore, the officer must be engaging in a course of conduct designed to further a proper policing purpose of the kind described by Lord Parker CJ in Rice v Connolly. The officer must be acting in good faith attempting to achieve that purpose. The conduct must be lawful; see B v DPP [2008] EWCH 1655 (Admin). Where it involves the use of force for the prevention of crime or the making of an arrest, the use of force will be lawful only if it is reasonable; section 3 of the Criminal Law Act 1967. Where it involves the use of a power under the Police and Criminal Evidence Act 1984, the use of force will, again, only be lawful if it is reasonable; section 117 of that Act. It is not necessary for the officer to be acting in the execution of her duty that she is using force or exercising any specific police power. If she is, she must be acting lawfully. If she is not, for example by making the request to the appellant that she should stop blocking the path of the vehicles and move out of the way, her conduct must be rational in the Wednesbury sense. This level of scrutiny does not mean that every error or unlawful act by a police officer will confer immunity on those who may try to obstruct her. In Metcalf v Crown Prosecution Service [2015] EWHC 1091 (Admin) police officers had attended an address following reports of a domestic disturbance between the appellant and another. Both men were arrested. The appellant objected as the other individual was escorted away by the two officers and placed in the back of a police car. He tried to block the officers' way and was repeatedly told to stop interfering and to move away. He tried to open the rear door of the police car and to stick his head into the vehicle. At one point, one of the officers attempted to stop the appellant speaking to the other man by barring his way and then by pushing him out of the way. At trial, the appellant made a submission of no case to answer on the basis that the officer had assaulted him when he pushed him. Relying on Wood v DPP [2008] EWHC 1056 (Admin) [2008] Po. L.R. 227, he argued that the officer's alleged unlawful conduct meant that he was not acting in the execution of his duty, with the consequence that the appellant's own conduct could not amount to obstruction. The Divisional Court, Burnett LJ and Stewart J, upheld that conviction on the basis that the push was not unlawful. Burnett LJ said this:-

"13 The task upon which P.C. Upshon was engaged, both before and after the push, was in securing one of the arrested men by placing and keeping him in the police car with a view to transporting him to a police station. The officer and his colleague were also engaged in a more general sense in seeking to keep the peace. These aspects encompass the "duty" P.C. Upshon was in the process of executing.

14 In my judgment it matters not whether the push was lawful or unlawful in determining the answer to the question whether the appellant was wilfully obstructing P.C. Upshon in the execution of his duty. The push clearly had no bearing on the question whether the appellant's conduct before that time amounted to wilful obstruction. On the findings of the magistrates it did. I am unable to see how an unlawful push could retrospectively render conduct lawful, which was otherwise criminal. But equally, if the push were unlawful it does not follow that P.C. Upshon was any the less acting in the course of the execution of his duty thereafter in dealing with the arrested man in the car. Even on that hypothesis, a person who has been assaulted by a police officer is not liberated from the application of the criminal law prohibiting wilful obstruction of a constable (including that constable) in the execution of his duty. The assault itself could not be characterised as being part of the execution of the officer's duty. That is why Fraser Wood was entitled to resist when he was restrained. But he would not, for example, have been entitled to block the officers with a view to preventing them making a lawful arrest, dealing with an incident of disorder or executing a search warrant. That would have amounted to wilful obstruction of the officers in the execution of their duty. So too here, even if the appellant was the victim of an assault it provides him with no defence to a charge of obstructing the officer in the execution of his duty regarding the arrested man in the car."

27. In this case the inspector's request or direction to the appellant to move could not in the circumstances amount to anything which was prima facie any unlawful interference with the appellant's liberty or property. Indeed it was accepted on behalf of the appellant that had the officer's direction been given in different terms, she might or would have moved. This is a clear indicator that the matter raised is one of form rather than of substance. The inspector's duty in this case was to secure the lawful passage of the vehicles across the land. Put differently, she reasonably perceived that her task was to prevent any person from committing crime by unlawfully obstructing their passing. Her plan was first to request the appellant and her associates to move and, if they did not, to arrest them for an offence under the Highways Act 1980 and to move them by force. By refusing to move when asked to do so, the appellant gave her reasonable grounds to suspect that she intended to continue to obstruct the highway wilfully. That same act of wilful obstruction would not only obstruct the highway but also the inspector in the execution of her duty to clear it. Accordingly she could choose which offence to arrest for, and chose both. The issue is whether that plan was reasonable and lawful. There was nothing unlawful about asking the appellant to move and informing her that if she does not she will be committing a criminal offence. It would not, however, be reasonable for a police officer to do that unless she reasonably believed that it was true and was acting in good faith. The request carried an express or implied threat that an arrest would follow unless there was compliance. Whether that threat was reasonably made depended on whether any arrest would be lawful.
28. The question therefore arises as to whether the fact that the officer had the wrong offence in mind affects the position. I return to Lord Simonds' observations in Christie v Leachinsky to the effect that it is not an essential condition of lawful arrest that the constable should formulate any charge at all, much less a charge which may ultimately be found in the indictment. What is required is that the arrested person be told what is the act for which he is being arrested. Lord Simonds said:

"This is I think, the fundamental principle, viz., that a man is entitled to know what, in the apt words of Lawrence LJ, are "the facts which are said to constitute a crime on his part"."

29. More recently in Chapman v DPP [1989] 89 Cr App R 190 at page 197 Bingham LJ, as he then was, said:

"It is not of course to be expected that a police constable in the heat of an emergency, or while in hot pursuit of a suspected criminal, should always have in mind specific statutory provisions, or that he should mentally identify specific offences with technicality or precision. He must, in my judgment, reasonably suspect the existence of facts amounting to an arrestable offence of a kind which he has in mind."

30. That was a decision made in a context where at that time section 24(6) of the Police and Criminal Evidence Act required a constable to have reasonable grounds for suspecting that an arrestable offence had been committed before he could arrest without warrant. That particular provision has subsequently been amended, but the passage cited is consistent with what was said in Christie v Leachinsky about the absence of formality involved. Those authorities relate to the formalities of arrest, but it seems to me that there is no reason why similar principles should not apply to the directions of the officer in the phase immediately preceding arrest.
31. I therefore conclude that it was not necessary for the officer to have had the correct offence in mind at the time the direction to move was given. It was sufficient for the officer to have taken steps which reasonably appeared to her to be necessary for preventing crime. The fact that the officer in fact had an offence of which the appellant was not guilty in mind did not prevent her from taking steps which in the circumstances, as she believed them to be, reasonably appeared to her to be necessary for preventing crime.
32. In the light of the findings that the officer reasonably believed at the material time that the road was a public highway and that she had reasonable grounds to suspect that an offence was being committed I would hold that the officer was acting within the execution of her duty. In so concluding I take note of the finding that the officer had stated that she was aware that lorry drivers had permission to drive along the road. This has to be read alongside the finding that the judge accepted that nonetheless the officer had reasonably believed that the road was a highway.
33. In the light of the foregoing, I do not think it necessary to consider issues raised in relation to aggravated trespass.
34. I would dismiss the appeal. As to the questions posed in the Case, I would answer (a) by holding that the officer's mistake was a question of fact. As to (b) I would hold that the officer was not mistaken as to the power she was exercising. I would answer question (c) in the negative. I would answer the first, second and third parts of question (d) in the affirmative. I would answer question (f) in the negative and decline to answer questions (e), (g) and (h) as unnecessary to the decision in this appeal.

Mr Justice Edis :

35. I agree.