England and Wales High Court (Queen's Bench Division) Decisions

IN THE HIGH COURT OF JUSTICE
QUEEN'S BENCH DIVISION

		Royal Courts of Justice Strand, London, WC2A 2LL
		31/10/2014

Mr Justice Warby :

1. These two libel actions both arise from a now notorious incident at the gates of Downing Street on the evening of 19 September 2012 involving Andrew Mitchell MP, the then Government Chief Whip, and PC Toby Rowland, a member of the Diplomatic Protection Group.
2. There is to be a trial of preliminary issues on liability in both actions, starting on Monday 17 November 2014. The two main preliminary issues are, in each action, what natural and ordinary meaning(s) the words complained of bore, and whether in such meaning(s) they were substantially true.
3. On 23 and 24 October 2014 I conducted a pre-trial review (PTR). This judgment sets out my reasons for decisions I made at the PTR in relation to expert evidence, and in respect of an application to exclude certain factual evidence from the trial. It also deals with some points of detail arising from one of the other rulings I made at the PTR, concerning irrelevant material in witness statements.

The actions and the issues

4. The following is an abbreviated account of the issues, focusing on those which are of significance to the decisions mentioned above.
5. Mr Mitchell sues News Group Newspapers Ltd (NGN) in respect of an article published in The Sun on 21 September 2012 headed "Cabinet Minister: Police are Plebs". Mr Mitchell complains that the article meant that he "was guilty of launching a grossly offensive and arrogant attack at Downing Street police officers on 19 September 2012 branding them as 'fucking plebs' and 'morons'."
6. NGN plead that the article was substantially true in this meaning or alternatively in the meaning that Mr Mitchell "arrogantly believed that he was too important to have to comply with Downing Street security rules, threatening, ranting and swearing in an abusive foul mouthed tirade at the police constables who asked him to do so".
7. At the heart of NGN's case is the account of events given by PC Rowland. According to him Mr Mitchell, having demanded but been denied the right to leave on his bicycle via the main Downing Street gates, lost his temper and said to PC Rowland "Best you learn your fucking place – you don't run this fucking government – you're fucking plebs."
8. Mr Mitchell denies "demanding" to be allowed to use the main gates, losing his temper, or using the words attributed to him by PC Rowland. He says that he asked politely to use the main gates and that what he said was "I thought you guys were supposed to fucking help us". He says those words were not spoken to or at PC Rowland, but muttered under his breath.
9. It is common ground that PC Rowland heard Mr Mitchell swear and that after that PC Rowland issued him with a verbal warning that if he did so again he would be arrested.
10. NGN's case is that as he left via the side gate Mr Mitchell said to PC Rowland "You haven't heard the last of this." Mr Mitchell accepts that he may have said words to the effect that he would pursue the matter the next day.
11. PC Rowland sues Mr Mitchell in respect of statements Mr Mitchell made in the broadcast and print media from December 2012 onwards, and at a press conference on 26 November 2013. PC Rowland complains that what Mr Mitchell said on these occasions meant, among other things, that PC Rowland had fabricated the allegation that Mr Mitchell called PC Rowland and/or police "fucking plebs" and used other offensive words; and that PC Rowland's log or record of the incident contained false evidence to his knowledge.
12. Mr Mitchell's Defence asserts that PC Rowland did fabricate his account of what Mr Mitchell said, and that he also fabricated a claim that these abusive comments were witnessed by several members of the public outside the Downing Street gates who looked visibly shocked by them. PC Rowland denies all of this. He maintains that as Mr Mitchell spoke the words he "had been conscious of several members of the public being in the vicinity on the Whitehall side of the barrier and noticed that they seemed shocked by what had occurred". This, he says, is why he gave warning that he would arrest Mr Mitchell if he continued to swear.

Expert evidence

13. At the CMC it was apparent that one or all parties might wish to apply for permission to adduce expert evidence at the trial. Two fields of expertise were identified as candidates: (i) phonetics and (ii) field of vision/trajectory analysis. I directed that any application should be made by 21 August 2014. By agreement between the parties however time was extended into September. On 16 September 2014 Mr Mitchell issued an application for permission to adduce evidence from two experts. On 19 September 2014 NGN and PC Rowland issued similar applications, seeking between them permission for two experts.
14. The first area of expertise proposed was phonetics, and the issue to which the evidence would go was identified as "The length of time that the 59 syllable exchange as alleged by PC Toby Rowland might reasonably have taken to enunciate." The proposition that lay behind Mr Mitchell's application to call expert phonetics evidence on this issue is one that I was told he had advanced on several occasions in the past outside the context of this action: that it is possible to prove by reference to CCTV of the events that night that he cannot have used the words that PC Rowland says he used. By the time his application was issued he had confirmed in Further Information given in both actions on 11 August 2014 that it is his case "that the incident … could not have taken place as alleged by PC Rowland, in particular by reason of the lack of available time, derived from the CCTV images." He stated that he relied on, among other things, "the time which the exchange would have taken, including pausing."
15. In summary, Mr Mitchell's case is that if one puts together PC Rowland's account, the CCTV footage of the incident, and evidence as to what others heard, it is clear that there is only a short period of time within which words could have been spoken by Mr Mitchell to PC Rowland; that this period of time is too short to contain the words that PC Rowland alleges were spoken by Mr Mitchell and PC Rowland; and that this can be proved by reliance on expert evidence in phonetics. Mr Mitchell says that experts in phonetics can assess with accuracy how long a given passage of speech is likely to take to enunciate. Studies have been undertaken into speech rates which, allowing for differing rates of speech, pauses and other variables, enable experts to identify a range of possible durations, it was submitted. Armed with samples of the speech of an individual whose speech or alleged speech is under examination, as is proposed here, the expert can provide an answer with considerable precision. This would be a far better means of addressing the issue than any attempt to do so armed only with a stopwatch, for example, it was said.
16. There was support for some of these points in the form of two reports commissioned from an expert in phonetics by Metropolitan Police Professional Standards in November 2013 for the purposes of their own investigations. These reports referred to and applied what is evidently a body of scientific study into the incident speech rates, and arrived at conclusions as to how long it would have taken for the words alleged by PC Rowland to be spoken.
17. Mr Mitchell wishes to rely on evidence from an expert in phonetics in the form of Professor Peter French, the Hon Professor in the Department of Language and Linguistic Science at the University of York, whose CV was exhibited to the witness statement in support of the application of 16 September. This included the information that Prof French has been involved as an expert in more than 5,000 cases. In answer to questions from me at the hearing, Mr Price maintained that the evidence would show that the time required to speak the 59 syllables cannot be reconciled with the CCTV and other evidence. The available time falls short by a considerable margin of what would be required, he said. The position of NGN and PC Rowland was that it was impossible for Mr Mitchell to prove this negative, and that there was sufficient time for the words to be spoken. They wish to call Professor Mark Liberman, Distinguished Professor of Linguistics at the University of Pennsylvania, to counter Mr Mitchell's case. I was provided with his CV.
18. Both parties were in a position to serve reports in very short order, it was said. At one stage it had been envisaged that exchange would take place on Friday 24 October. That, however, became the second day of the PTR. Exchange was therefore proposed for early the following week. That would allow some three weeks before the first day of trial. It was naturally envisaged that the expert evidence, if permission was granted, would not be given before the second week of trial at the earliest.
19. The first question to address on any application to call expert evidence must be whether the evidence is admissible. Section 3 of the Civil Evidence Act 1972 provides that:

"3 (1) Subject to any rules of Court made in pursuance of this Act, where a person is called as a witness in any civil proceedings, his opinion on any relevant matter on which he is qualified to give expert evidence shall be admissible in evidence...

(3) In this section "relevant matter" includes an issue in the proceedings in question."

20. In Barings Plc v Coopers & Lybrand (No 2) [2001] EWHC 17 (Ch); [2001] PNLR 22 Evans-Lombe J reviewed the authorities and extracted from them at [45] the following propositions:

"expert evidence is admissible under section 3 of the Civil Evidence Act 1972 in any case where the Court accepts that there exists a recognised expertise governed by recognised standards and rules of conduct capable of influencing the Court's decision on any of the issues which it has to decide and the witness to be called satisfies the Court that he has a sufficient familiarity with and knowledge of the expertise in question to render his opinion potentially of value in resolving any of those issues."

21. There was no contest between the parties on whether these requirements were met in relation to the two proposed experts, but it remains a matter for the court to decide. I had no difficulty in concluding that phonetics is a recognised academic discipline which encompasses the scientific study of rates of speech, and is governed by recognised standards of conduct. It is sufficiently clear that the chosen witnesses each possess sufficient knowledge to enable them to provide evidence of speech rates applicable to this case which has potential value to the trial judge. The issue to which such evidence would go is on any view the main issue in both actions. The account of the evidence that would be given satisfied me that it was capable of influencing the court's decision on that issue.
22. The court's approach to deciding whether it should permit expert evidence, assuming it to be admissible, was also addressed by Evans-Lombe J in his analysis in the Barings case at [45], where he said this:

"Evidence meeting this test can still be excluded by the Court if the Court takes the view that calling it will not be helpful to the Court in resolving any issue in the case justly. Such evidence will not be helpful where the issue to be decided is one of law or is otherwise one on which the Court is able to come to a fully informed decision without hearing such evidence."

23. The court must also have regard to CPR 35.1 which provides that "Expert evidence shall be restricted to that which is reasonably required to resolve the proceedings."
24. Here, the trial judge could arrive at a decision on the central issue in these cases without reference to expert or any analysis of speech rates, but instead by assessing the witnesses, their credibility, and the probabilities in the light of all the other evidence including the CCTV. It is naturally a matter for concern that the position adopted on one side of the issue is that evidence of this kind, if adduced, will be inconclusive. In that event, the evidence would not have been helpful but its admission would have been wasteful. It does not follow, however, nor could I take the view, that this evidence will not be helpful in resolving the issue justly.
25. The case for Mr Mitchell, as explained by his Leading Counsel, is that the evidence would not only be helpful but it would be conclusive in his favour. I was in no position to dismiss that as a real possibility. Where a party to civil litigation credibly alleges that expert evidence he has obtained will show that his opponent's case cannot be true, that must be a powerful factor in favour of permitting the evidence to be led. It also seemed to me that there is a real prospect that, if not conclusive, objective evidence of this kind would help the trial judge reach a conclusion as to the probabilities on the central issue. The evidence is potentially of value, perhaps very great value, in resolving the issues.
26. The case for admitting the evidence is bolstered by the fact that these cases have an important public dimension and have attracted considerable public attention. It is highly desirable that their outcome should be one that commands public confidence. The process should not be vulnerable to the charge that one or the other party has been unreasonably denied an opportunity to lead evidence which, had it only been heard, would have altered the outcome.
27. CPR 35.1 imposes a duty on the court to restrict expert evidence to that which is reasonably required. I do not, however, read this as imposing a test of absolute necessity. A judgment has to be made in the individual case, and it has to be made before the evidence is heard and evaluated. My conclusion was that evidence which it is credibly said could conclusively determine the single most important issue in the case meets the criterion in the rule.
28. For those reasons I granted permission to each party to lead expert evidence on the issue identified above, Mr Mitchell's evidence to come from Professor French and the evidence for NGN and PC Rowland to come from Professor Liberman. The order makes provision for the exchange of reports and for a meeting of the experts before trial, the purpose being to identify areas of agreement and disagreement.
29. The second topic identified at the CMC as a potential area for expert evidence was "field of vision/trajectory analysis". The issue on which Mr Mitchell and then the other parties all sought permission to call expert evidence when they issued their application notices was "the number of members of the public it was possible for Toby Rowland to have had in his field of vision before the point at which he claims he gave Andrew Mitchell MP a verbal warning pursuant to the Public Order Act 1986."
30. The position taken by Mr Mitchell on this issue is similar to that which he adopted in relation to phonetics evidence. He does not merely say that his evidence can show that it is unlikely that PC Rowland saw what he said he saw. He asserts that he can prove by expert evidence that PC Rowland cannot have seen several visibly shocked members of the public before giving the public order warning.
31. The evidence of Ms Middleton of Mr Mitchell's solicitors, filed in support of this application on 16 September 2014, identified optometry as the area of expertise appropriate for this issue. The intended methodology was outlined by Ms Middleton. She explained that the CCTV would be used to plot the locations and head positions of the main protagonists. An expert could then use this information, alongside available data relating to peripheral vision, to recreate geometrically PC Rowland's field of vision at a given point of time.
32. Ms Middleton's statement did not identify the intended expert. It appears on the face of it that at the time of her statement he had not been identified. By the time of the hearing Mr Mitchell's chosen expert had been identified as Professor David Whitaker of Bradford School of Optometry and Vision Science, whose CV was provided to me when the parties' skeleton arguments were supplied. Prof Whitaker is plainly a highly qualified optometrist. As with the phonetics experts, it was apparent that a report was ready or imminent and it was said that exchange could take place early the week after the PTR.
33. The applications of NGN and PC Rowland for expert evidence on this issue which were made on 19 September 2014 confirmed their agreement with Mr Mitchell that such evidence was likely to assist the court. The applications did not identify the name of their intended expert or the nature of his or her expertise. By the time of the hearing both items of information had been provided.
34. The skeleton arguments for NGN and PC Rowland, dated 22 October 2014, named the witness as Andrew Postlethwaite, and described him as an expert in forensic virtual reconstructions. It was said that "virtualisation" of the scene was commonly used in criminal trials. No CV was provided at that point. Passages from it were read to me on the first day of the PTR. On the second day of the PTR I was provided with a copy of the CV for Mr Postlethwaite.
35. This showed that he has 20 years' experience in the reconstruction of crime and crime scenes, working for prosecution and defence teams, the Independent Police Complaints Commission (IPCC) and private individuals. In the 1990s he worked for the Metropolitan Police reconstructing crime scenes. He believed he was the first to present, in 1994, three dimensional computer graphics in court, at the Old Bailey. He had been instructed in 550 cases including a large number of well-known criminal trials, as well as inquests, two IPCC inquiries and the Public Inquiry into the Dunblane Primary School shootings. In this last inquiry he had provided Lord Cullen and expert assessors with an animation of the killer, Thomas Hamilton, moving through the school, showing his view as he carried out the shootings. Mr Postlethwaite's qualifications as an expert had been subjected to vigorous challenge in the 1994 Old Bailey trial, but had been accepted. The few subsequent challenges made had failed.
36. I was also provided with a summary of Mr Postlethwaite's methodology for the present case. This made clear that he had made two visits to Downing Street, and carried out a virtual reconstruction of the scene at the gates. He had created virtual CCTV cameras and used the CCTV footage to plot the positions of PC Rowland and members of the public who were seen on the CCTV. He had then produced a three dimensional version of what was shown by the CCTV cameras. To determine what could be seen by PC Rowland at any point during the relevant period he had applied a 120 degree field of vision that being the minimum requirement for police officers.
37. It became apparent that, as with the other witnesses, Mr Postlethwaite's evidence in the form of a report together with the virtual reconstruction was either in existence or in its final stages and would be ready for exchange early the following week. I was told that he had been instructed in late August or early September.
38. Mr Price accepted that Mr Postlethwaite was an expert but, he said, an expert in virtual reconstructions and not the discipline of optometry which had been advertised by Mr Mitchell as the one in which he intended to obtain an expert report. The decisions of NGN and PC Rowland to instruct a witness in a different discipline, and to proceed with that instruction without any notice to Mr Mitchell until exchange of Skeleton Arguments also gave rise to understandable concern on behalf of Mr Mitchell.
39. The primary focus of that concern was the risk that if permission was granted the experts might meet but as ships passing in the dark, neither having any knowledge of the other's speciality. To the extent that the experts failed to agree, Mr Price would be hampered in or possibly disabled from properly testing his opponents' evidence in this respect. It was submitted that even assuming Mr Postlethwaite to have relevant expertise it would be unfair to Mr Mitchell to give permission.
40. Mr Browne and Mr Millar, in riposte, maintained that Mr Postlethwaite's report fell within the scope of the issue that had been proposed as the subject of expertise, and was surely the better kind of evidence. Three dimensions are better than two, submitted Mr Browne. Counsel also complained that the nature of the report to be provided by Prof Whitaker remained wholly unclear. Mr Browne identified what he suggested were obscure specialities listed in Prof Whitaker's CV, suggesting that on the face of it his expertise might be too refined to assist in what was in the end an exercise in reconstruction.
41. This was clearly a highly unsatisfactory set of circumstances. I nonetheless decided to grant permission to both parties, for these reasons.
42. Taking Mr Mitchell's application first, the expertise of Prof Whitaker was apparent from his CV. I was satisfied that optometry and in particular peripheral vision are recognised fields of expertise, in relation to which Prof Whitaker is a qualified expert. The task he was to undertake was adequately described in Ms Middleton's statement. I saw no reason to doubt that Prof Whitaker is able to perform that task. Mr Mitchell says that he can through this evidence demonstrate not just that PC Rowland probably did not but that PC Rowland cannot have seen visibly shocked members of the public before giving the warning. I could not at this stage reject that proposition, advanced through Leading Counsel. Even if the evidence falls short of proving impossibility there is a real prospect it will assist in resolving the probabilities. It appears to be evidence that is potentially of value in resolving this important issue. It is reasonably required for reasons similar to those identified above in respect of the phonetics evidence. It can be served in a short space of time, with sufficient time before trial.
43. The application of PC Rowland and NGN was distinctly unattractive given their very late disclosure of a decision apparently made nearly two months earlier to instruct an expert in an entirely different discipline from the one which they knew Mr Mitchell had chosen. The potential for unfairness to Mr Mitchell was a significant consideration. However, Mr Postlethwaite appeared to me to possess considerable expertise, recognised by courts on a number of occasions, in reconstructing events with precision. He was in my judgment sufficiently qualified within the meaning of s 3 of the Civil Evidence Act 1972 to provide the court with opinion evidence, by means of a report and 3D computer graphics, on the issue of what PC Rowland could have seen. I found that his evidence would be potentially helpful in resolving whether PC Rowland could have seen members of the public and if so where and when. If his evidence was excluded the court would be left with no cross-check on Prof Whitaker's conclusions. I concluded that any risk of unfairness to Mr Mitchell could be adequately catered for by the court making due allowance in assessing the weight to give to Mr Postlethwaite's conclusions, to the extent they differ from those of Prof Whitaker.
44. I add that PC Rowland and NGN have made no complaint of being hampered or disabled from cross-examining Prof Whitaker on account of having no optometrist of their own. They could hardly make such a complaint in the circumstances. Should any claim be made in future to recover costs they incurred in obtaining help from an optometrist for the purposes of cross-examination that would have to be looked at very carefully indeed.

Application to exclude evidence

The evidence and the application

45. On 24 July 2014 PC Rowland served his Reply. It contained at paragraph 5.28 a list of what were described as "Previous similar instances of the Defendant behaving in a high handed and rude manner towards police officers". On 4 September 2014 NGN amended their Defence to Mr Mitchell's claim. In the process they added a corresponding plea of "previous similar incidents demonstrating [Mr Mitchell's] high handed and rude manner towards police officers and demonstrating his cavalier attitude towards security and the security policies in place." PC Rowland amended his Reply on 14 October 2014 to add to his list of "previous similar instances."
46. By the time of the hearing the total number of alleged incidents relied on by PC Rowland and NGN was some seventeen, dating from November 2005 to September 2012. Witness statements have been served in support of each. The alleged incidents all involve some form of encounter with police officers. The majority are said to have occurred at security gates or barriers, either at the Palace of Westminster or at Downing Street, when Mr Mitchell was faced with some impediment to free movement imposed by police officers carrying out security duties.
47. It is said that when faced with such impediments Mr Mitchell on one occasion said "I'm a Member of Parliament and I'm too important to stop for you" and insulted the officer concerned as a "little shit". On a number of other occasions he is said to have proclaimed his status as a Cabinet Minister or as Chief Whip, to have acted in a demanding way, and to have expressed himself in ways which were abrupt, arrogant, rude, condescending, patronising or sarcastic. On some of those occasions he is said to have complained or threatened to complain about the officers' conduct. The case for NGN and PC Rowland is that the officers were merely doing their duty.
48. There are in addition two alleged incidents said to have taken place on official visits to Africa during 2011, when Mr Mitchell was Secretary of State for International Development. It is alleged that in April 2011, in Djerba, Mr Mitchell spoke sarcastically and patronisingly to a police officer, responding to a statement by the officer with the words "that's a bit above your pay grade, Mr Plod". In August 2011, on a visit to Kenya, Mr Mitchell is said to have responded to an unwanted change of itinerary with a "foul-mouthed tirade" addressed at police protection officers. He is alleged to have claimed a right to be "treated like royalty".
49. By an application notice dated 17 October 2014 Mr Mitchell applied for "an order excluding any evidence concerning the alleged 'similar incidents'", save for two such matters. The grounds of the application were that the evidence under attack "(i) is inadmissible; alternatively (ii) is excluded under CPR 32.1 as similar fact evidence, the probative value of which is outweighed by its potential for causing unfair prejudice and places a disproportionate burden on Mr Mitchell and raises collateral issues which are disputed and difficult or impossible to resolve." The two matters excluded from the scope of the attack were events which Mr Mitchell accepted were relevant, but for reasons other than any alleged similarity to those of 19 September 2012.
50. The application to exclude the evidence had been foreshadowed in Mr Mitchell's Amended Reply to NGN's Amended Defence, served on 22 September 2014. This asserted that the alleged incidents were irrelevant to and did not assist the court in relation to the issue of whether Mr Mitchell used what he calls "the toxic phrases" on 19 September 2012. The case for NGN and PC Rowland about the similar incidents was said to be fully consistent with Mr Mitchell's case about what he had said that night.
51. The Amended Reply also contained at paragraph 8A.5 an admission and averment that Mr Mitchell "on occasion was impatient and short-tempered with obstructive or otherwise unhelpful police officers because he felt that they were impeding his ability to do his job, and very occasionally he was (or may have appeared to have been) rude, or used swear words when speaking to those officers." The Amended Reply asserted that the case against Mr Mitchell in relation to the alleged incidents added nothing to this admission and averment. Mr Mitchell pleaded to the alleged incidents, but without prejudice to these points. He took a similar stance in correspondence, when consenting to the amendment of PC Rowland's Reply by letter of 9 October 2014, in which he made clear an intention to raise the matter at the PTR.

Principles

52. The controversial evidence relates to incidents other than the one which is at the centre of both actions. It was common ground at the hearing that the relevant principles are those concerned with the admission in civil cases of evidence of "similar facts", and that those principles are to be found in the decision of the House of Lords in O'Brien v Chief Constable of South Wales Police [2005] 2 AC 534. There the House identified a two stage process, holding that the test of admissibility of similar fact evidence in a civil case is one of relevance only; if that test is satisfied the court will consider whether the evidence should be admitted, as a matter of case management.
53. Lord Bingham said this at [3]-[4]:

"3 Any evidence, to be admissible, must be relevant. Contested trials last long enough as it is without spending time on evidence which is irrelevant and cannot affect the outcome. Relevance must, and can only, be judged by reference to the issue which the court (whether judge or jury) is called upon to decide. As Lord Simon of Glaisdale observed in R v Kilbourne [1973] AC 729, 756:

"Evidence is relevant if it is logically probative or disprobative of some matter which requires proof ... relevant (i e logically probative or disprobative) evidence is evidence which makes the matter which requires proof more or less probable."

4 That evidence of what happened on an earlier occasion may make the occurrence of what happened on the occasion in question more or less probable can scarcely be denied. If an accident investigator, an insurance assessor, a doctor or a consulting engineer were called in to ascertain the cause of a disputed recent event, any of them would, as a matter of course, inquire into the background history so far as it appeared to be relevant. And if those engaged in the recent event had in the past been involved in events of an apparently similar character, attention would be paid to those earlier events as perhaps throwing light on and helping to explain the event which is the subject of the current inquiry. To regard evidence of such earlier events as potentially probative is a process of thought which an entirely rational, objective and fair-minded person might, depending on the facts, follow. If such a person would, or might, attach importance to evidence such as this, it would require good reasons to deny a judicial decision-maker the opportunity to consider it. For while there is a need for some special rules to protect the integrity of judicial decision-making on matters of fact, such as the burden and standard of proof, it is on the whole undesirable that the process of judicial decision-making on issues of fact should diverge more than it need from the process followed by rational, objective and fair-minded people called upon to decide questions of fact in other contexts where reaching the right answer matters. Thus in a civil case such as this the question of admissibility turns, and turns only, on whether the evidence which it is sought to adduce, assuming it (provisionally) to be true, is in Lord Simon's sense probative. If so, the evidence is legally admissible. That is the first stage of the inquiry."

54. Lord Phillips identified the test of admissibility thus, at [53]: "I would simply apply the test of relevance as the test of admissibility of similar fact evidence in a civil suit. Such evidence is admissible if it is potentially probative of an issue in the action." On this and other issues Lords Steyn, Rodger and Carswell agreed with Lords Bingham and Phillips.
55. The main considerations affecting the second, case management stage were identified by Lord Bingham at [5]-[6]:-

"5 The second stage of the inquiry requires the case management judge or the trial judge to make what will often be a very difficult and sometimes a finely balanced judgment: whether evidence or some of it (and if so which parts of it), which ex hypothesi is legally admissible, should be admitted. For the party seeking admission, the argument will always be that justice requires the evidence to be admitted; if it is excluded, a wrong result may be reached. In some cases, as in the present, the argument will be fortified by reference to wider considerations: the public interest in exposing official misfeasance and protecting the integrity of the criminal trial process; vindication of reputation; the public righting of public wrongs. These are important considerations to which weight must be given. But even without them, the importance of doing justice in the particular case is a factor the judge will always respect. The strength of the argument for admitting the evidence will always depend primarily on the judge's assessment of the potential significance of the evidence, assuming it to be true, in the context of the case as a whole.

6 While the argument against admitting evidence found to be legally admissible will necessarily depend on the particular case, some objections are likely to recur. First, it is likely to be said that admission of the evidence will distort the trial and distract the attention of the decision-maker by focusing attention on issues collateral to the issue to be decided. This is an argument which has long exercised the courts (see Metropolitan Asylum District Managers v Hill (1882) 47 LT 29, 31, per Lord O'Hagan) and it is often a potent argument, particularly where trial is by jury. Secondly, and again particularly when the trial is by jury, it will be necessary to weigh the potential probative value of the evidence against its potential for causing unfair prejudice: unless the former is judged to outweigh the latter by a considerable margin, the evidence is likely to be excluded. Thirdly, stress will be laid on the burden which admission would lay on the resisting party: the burden in time, cost and personnel resources, very considerable in a case such as this, of giving disclosure; the lengthening of the trial, with the increased cost and stress inevitably involved; the potential prejudice to witnesses called upon to recall matters long closed, or thought to be closed; the loss of documentation; the fading of recollections. It is, I think, recognition of these problems which has prompted courts in the past to resist the admission of such evidence, sometimes (as, perhaps, in R v Boardman [1975] AC 421) propounding somewhat unprincipled tests for its admission. But the present case vividly illustrates how real these burdens may be. In deciding whether evidence in a given case should be admitted the judge's overriding purpose will be to promote the ends of justice. But the judge must always bear in mind that justice requires not only that the right answer be given but also that it be achieved by a trial process which is fair to all parties."

56. Lord Phillips' approach was similar. At [54]-[56] he identified considerations which the court would need to have in mind in deciding whether as a matter of discretion to admit evidence or cross-examination as to collateral issues. These included the need for proportionality and expedition, whether the evidence is likely to be relatively uncontroversial, and whether its admission is likely to create side issues that unbalance the trial and make it harder to see the wood for the trees. He added that the judge would have well in mind the considerations which concerned the House of Lords in Metropolitan Asylum District Managers v Hill 47 LT 29.
57. In that case, as pointed out by Lord Phillips at [44]-[45], the House had expressed concern at the prospect that the admission of evidence of collateral facts might prevent trials from being kept within a practical and manageable compass. With this concern in mind, Lord Watson had proposed that two conditions would need to be satisfied before collateral facts should be admitted as evidence to prove a matter in dispute. The first was that the collateral fact would "when established be capable of affording a reasonable presumption or inference as to the matter in dispute". The second was that the evidence should be "reasonably conclusive [as to the collateral fact] and will not raise a difficult and doubtful controversy of precisely the same kind as that which the jury have to determine".
58. Mr Price placed considerable emphasis on these two conditions in his submissions. I accept of course that the probative value of the alleged collateral facts and the likely nature, scope and outcome of any dispute about them are important considerations, when making case management decisions. I do not consider, however, that these passages from the speech of Lord Watson are to be treated as if they were in a statute or represent rigid rules governing the exercise of the discretion to admit evidence of relevant collateral facts. As Lord Phillips observed in O'Brien at [46], what Lord Watson was doing in this passage was "contemplating that the trial judge would have a discretion to shut out evidence of collateral facts in the interests of keeping the trial manageable. He was not propounding an inflexible rule of admissibility."

Discussion

59. Mr Browne submitted that it was a conclusive answer to Mr Mitchell's application that he had not objected when these matters were first raised in PC Rowland's Reply on 23 July 2014, and that the matters had also been pleaded by NGN before objection was raised. I did not find that a persuasive submission. It was not said that Mr Mitchell's delay had caused prejudice to Mr Rowland or NGN, nor does that appear likely. Mr Mitchell's objection to reliance on evidence of these matters has been expressed since 22 September 2014 when he served his Amended Reply in the NGN action. That was some three weeks before the exchange of witness statements. All the witness statements relied on by NGN and PC Rowland in support of the "similar incidents" were made and served after that. Even if some prejudice had been caused in the form of additional cost that ought not to be a basis for admitting evidence which on a proper analysis is irrelevant, or evidence which it would otherwise be appropriate to exclude as a matter of case management. I therefore considered the merits of the application.
60. The starting point must be to consider relevance, for which purpose it is necessary to identify "the matter which requires proof", to use Lord Simon's words in R v Kilbourne. Mr Price's submission was that the matter requiring proof is, quite simply, that Mr Mitchell used the "toxic words" attributed to him by PC Rowland.
61. Whether Mr Mitchell used the "toxic words" is of course central but (assuming the matter is not resolved by expert evidence) that allegation must be considered in its context. To assess whether it is probable that Mr Mitchell spoke those words the court will need to consider the whole sequence of events at the Downing Street gates that evening, and the differences between the competing accounts of Mr Mitchell's behaviour. There are areas of dispute about the detail that may be important.
62. NGN's Defence alleges that Mr Mitchell approached the Downing Street gates identifying himself as Chief Whip and demanded to be allowed to leave through the main gates. He continued to do so when told that according to security rules officers could not open the main gates for cycles, so it is alleged, ignoring requests to comply with the rules. It is said that when PC Rowland approached him he seemed agitated, continued to refuse to comply with requests to leave by the side pedestrian gate, reiterating his status as Chief Whip. He is alleged to have then walked towards the side gate, lost his temper and spoken the "toxic words", and then left announcing that PC Rowland hadn't heard the last of it.
63. Mr Mitchell denies ignoring officers' requests, or "demanding" to be allowed to cycle out. He says he "simply and politely asked to be allowed to do so" and that he said "please open the gates. I am the Chief Whip; I work here at number 9". He denies losing his temper, though he does admit to becoming "frustrated at being obstructed" and to swearing about the officers under his breath. He makes no concession that he was angry.
64. PC Rowland's case is to the same effect as that of NGN. He adds that throughout the incident he was calm, but Mr Mitchell "appeared agitated and was unjustifiably rude and high-handed" to PC Rowland in particular. A witness summary in respect of one of the other officers at the Downing Street gates that night states that Mr Mitchell was "clearly furious".
65. Having identified areas of difference in the rival cases, the next question is whether, in relation to those differences, the "similar incidents" are probative of the case for NGN and PC Rowland. Mr Price's submission was to the effect set out at 50 and 51 above: that the incidents are equivocal or neutral as between the two versions of events, and take the matter no further than the admission and averment in Mr Mitchell's Amended Reply. Mr Millar submitted that the incidents are evidence of a propensity or tendency on Mr Mitchell's part to push at the enforcement of security rules by junior police officers and to react adversely – testily or angrily – and to threaten consequences. Although the degree of anger and the degree of offensiveness were greater on 19 September 2012 than on previous occasions, his reactions bore similarities to his behaviour on previous occasions. To that extent these were incidents of an "apparently similar character" to the incident in issue. He submitted that, looked at as a body of evidence, the evidence of those incidents goes beyond what Mr Mitchell has been prepared to admit and that if established they are potentially probative of the case for NGN and PC Rowland.
66. I accepted the submissions of Mr Millar, in respect of a majority of the alleged incidents. I asked myself whether the evidence, assuming it provisionally to be true, might lead to the conclusion that events on the evening of 19 September 2012 were more likely to have unfolded in the way alleged by PC Rowland and NGN, rather than as alleged by Mr Mitchell. I concluded that the answer was that it might.
67. Looked at collectively the evidence of Mr Mitchell's encounters with police over cycle access at the Palace of Westminster, and cycle entry to and exit from Downing Street portrays a course of dealings in which Mr Mitchell has repeatedly asserted his status, engaged in confrontation, and, on a number of occasions, behaved in a rude and condescending way to police officers. One of the alleged incidents – the one of November 2005 - involves an explicit proclamation that he was too important to stop for the officer, and a direct insult addressed to the officer involved, under minimal if any provocation. The alleged incidents in Africa, if true, might show a hot temper, the use of foul language when provoked, a strong sense of superior status, and a condescending attitude to police officers.
68. The evidence seemed to me potentially to throw light on Mr Mitchell's attitude and reaction when impediments are placed in his way by police officers and to show a more complex picture, materially different from Mr Mitchell's version of events on 19 September 2012 and from the occasional impatience and short temper and very occasional rudeness on other occasions which is admitted to by Mr Mitchell.
69. There were, however, six allegations that I ruled out as they seemed to me to fall short of the threshold of potential probative value. Allowing for the two alleged incidents which Mr Mitchell accepts are relevant for other reasons, that left nine disputed "similar incidents", involving some eleven witnesses.
70. As to the exercise of the discretion to exclude relevant evidence, Mr Price submitted that there was potential for unfairness to Mr Mitchell as he could not remember most of the incidents, and that the probative value of the evidence did not outweigh the unfair prejudice which its admission would cause. He said that the evidence raised collateral issues which could not fairly be resolved with confidence. He conducted a detailed analysis of each alleged incident with a view to illustrating these points.
71. In the course of his submissions Mr Price invited me to reach conclusions as to the credibility of at least some of the allegations against Mr Mitchell. He submitted, for instance, that the suggestion that Mr Mitchell had said in November 2005 that he was too important to stop for a police officer "simply lacks any credibility". In relation to the evidence of incidents of 2011 in Africa he submitted that the officer who claims to have witnessed the events "is not a witness on whom the court can rely".
72. My conclusion was that the evidence that I found to be relevant should be admitted. I did not consider it appropriate to rule on issues of credibility at the PTR. The evaluation of the evidence is a matter for trial. However, I did not believe the trial would be distorted or unbalanced by the admission of this evidence. The incidents alleged were all relatively brief, and the evidence in support of them quite narrowly confined. The evidence, if properly managed at trial, should not take up a great deal of time.
73. I did not consider there would be unfair prejudice to Mr Mitchell. He has been able to plead a positive case as to the nature and extent of his adverse reactions to what he perceived as obstruction from police officers. His witness statement addresses specifically the allegations about the November 2005 incident at the Palace of Westminster and about his conduct on the African visits. Mr Price's submissions showed that he is able on behalf of Mr Mitchell to test much of the evidence by reference to documents. The trial judge can give appropriate weight to the evidence, making due allowance for the passage of time and any restrictions on Mr Mitchell's ability to challenge what is said. Moreover, Mr Mitchell will be able to rely on the substantial number of witness statements he has obtained and served containing evidence to the effect that he is habitually courteous and respectful towards others, including the police. This is an aspect of the evidence to which I refer further below.

Objections to witness statements

74. NGN and PC Rowland applied for a ruling that parts of the witness statements of Mr Mitchell and his witnesses should be removed on the grounds that they were irrelevant to the preliminary issues, or otherwise inadmissible. As I said at the time, this was an unusual application in relation to what will be a trial by judge alone. Nonetheless I heard the application, and ruled on issues of principle. I concluded that evidence relevant only to the damage allegedly caused by the words of which Mr Mitchell complains had no bearing on the preliminary issues, which do not include any issues of damage. As there were substantial passages covering this topic, with no other apparent relevance, I concluded that in the circumstances of this case there should be an editing process in relation to the versions of the statements for use at trial. For the purposes of the trial, the attention of the parties, the judge, reporters and observers should be focused on what is relevant to the issues being tried.
75. Some issues of detail were left over to allow for written submissions on behalf of Mr Mitchell. Having since had those submissions I am able to provide final conclusions. So far as Mr Mitchell's own statement is concerned, the passages which should be omitted from the version made available to the public at trial and to the trial judge are those objected to by NGN and PC Rowland, with the exceptions identified in the schedule to this judgment. As for the statements of Mr Mitchell's witnesses, my ruling was that passages containing assessments, based on their knowledge of his behaviour, of the likelihood of Mr Mitchell using the words alleged should not be ruled out of their statements. The dividing line between what is and is not admissible in this respect is not always clear cut. It is appropriate to leave until trial the assessment of where that line is drawn. That leaves controversy over just one paragraph in the statement of Lord Turner. Mr Mitchell accepts, in the light of my ruling, that this paragraph should be edited. The passages to remain are identified in the schedule.
SCHEDULE

Statement	Objections not upheld - passages to remain
Andrew Mitchell	46 – whole paragraph; 68 – whole paragraph; 70-71
Lord Turner	First sentence. Second sentence except "has caused him …" to "… because it".