Evidence which could be given orally
Waksman J started his short published case management judgment in PCP Capital Partners LLP & Anor v Barclays Bank Plc  EWHC 646 (Comm) (12 March 2020) as follows:
' This is a PTR and it seems to me that if there are problems with anyone's witness statements in terms of material that should not be there and which is likely to prove a distraction at trial, or increase the time spent on that statement, either by the judge or by counsel or anyone else, or which could increase the cross-examination unnecessarily, it is my job, as the judge who will be trying this case, to seek to do something about it.'
From the report it is not possible to tell what the issues are in the case. Though details are not given in the judgement, there were matters in both parties’ statements which made the judge unhappy. This caused him to tell the parties – or their lawyers – to go away and edit the statements before coming back for the trial in a few weeks’ time.
For family proceedings, the procedure for dealing with evidence is mostly in Family Procedure Rules 2010 (FPR 2010), Pt 22. Thus a witness statement is a summary of the evidence that a person ‘would be allowed to give orally’ (FPR 2010, r 22.4(1)), it must comply with the details in Practice Direction PD22A (which deals mostly with formatting of the statement) and it must be signed with a statement of truth (FPR 2010, Pt 17). At any final hearing oral evidence is given; but at all other hearings evidence is in writing. Normally this will be by statement, but where specifically required it must be by affidavit or affirmation.
Relevance to issues
What a person ‘would be allowed to give orally’ (per rule 22.4(1)) is critical to all this. It is what concerned Waksman J. For example, evidence which is not relevant to an issue in the case should be excluded in drafting of any statement. Thus for anyone drafting the statement a clear definition of what the issues for trial should be provided, and perhaps reproduced as statements in the statement.
One of the witnesses in the PCP case was a Mr Varley. Waksman J required his advisers to revise his statement on the following grounds:
' There are definitely elements of Mr Varley's witness statement which should not be there, in particular because, in truth, they are no more than arguments or simply bringing into the witness statement contents of the documents and nothing more than that, documents to which Mr Varley was not a party.
 … It is not permissible here for [Mr Varley] him to comment where he has, after the event, been shown transcripts of calls between other people to say what has happened and what they indicate. What these transcripts indicate will ultimately be a matter for the judge, and Mr Varley is in no better position than anyone else to say what they do or should mean.'
Witnesses should not argue matters of law which are for the witness’s advocate at trial. A witness statement should only contain hearsay where proper notice of the party’s intent to rely on it has been given (Civil Evidence Act 1995, s 2(1)(a); FPR 2010, r 23.2(1)). If certain documents only which are covered by privilege are referred to the witness must be warned that all documents in a series covered by privilege may be required also (see eg Re D (Care Proceedings: Legal Privilege)  EWCA Civ 684,  2 FLR 1183: a mother in care proceedings had included in her statement reference to a note she had prepared during a meeting with solicitors: she was required produce the whole of the attendance note).
Control of evidence
A pervasive of rule dealing with evidence and how it may be case managed was introduced by Civil Procedure Rules 1998, r 32.1. Rule 32.1 is reproduced in FPR 2010, r 22.1 which includes ‘giving directions as to … the nature of the evidence which [the court’ requires to decide’ the issues before the court (rule 22.1(1)(b)). Evidence which comes within the categories covered by PCP might be excluded; evidence which is not relevant to an issue must generally be excluded; hearsay evidence may be excluded; evidence covered by privilege must be excluded save where a party entitled to the privilege has waived privilege – or is deemed to have waived it.
Subject to all this, the statement ‘is to stand as the witness’s evidence in chief’ (rule 22.6(2)) unless a party (or their advocate) has permission to ‘amplify [a] witness statement’ (rule 22.6(3)(a)): evidence is given as to relevant facts which have occurred since the statement was signed (r 22.6(3)(b)); or the court gives permission (r 22.6(2)). It must be the case that court time could be saved if r 22.6 was adhered to; though it must be said that family proceedings do not make this easy to define. For example statements in financial provision proceedings are by Form E which does not fit easily into this framework; and in children proceedings statements may only be filed when the court directs.
Permission for expert evidence
The most critical aspect of control of evidence is in opinion (‘expert’) evidence, as defined for children proceedings only (Children and Families Act 2014, s 13) and FPR 2010, r 25.4(3) which, for present purposes, come to the same thing: that a report may only be put before the court where the report is ‘necessary to assist the court to resolve the proceedings’.
The scope of this provision was recalled by the Court of Appeal in Re AV (A Child) (Expert Report)  EWCA Civ 346 (5 March 2020). The judge had refused to permit the report of child psychiatrist on a three year old child who had lost three siblings in a fire and was subject to care proceedings. The parent’s appeal (with the Official Solicitor acting for the mother) was allowed. The options available for care and the extent of psychiatric damage to the child must be assessed fully, with the assistance of expert evidence, before the court could decide the case. Baker LJ explained his view:
' … A party applying for permission to appeal to overturn a case management decision made within the judge's discretion must cross a high threshold. It is also right to acknowledge that the judge's approach to the issue was very much in keeping with current thinking about the use of experts in family cases, now reflected in Children and Families Act 2014 s 13. Judges are expected to scrutinise carefully all applications for the instruction of an expert, and only allow them when satisfied that the expert's opinion is necessary to assist the court to resolve the proceedings justly. The judge unquestionably asked herself the right question. I am clear, however, that the answer she gave to that question was wrong.'