Lord Justice Jackson's reforms to the Civil Procedure Rules (CPR)  enabled judges to take a more active part in case management: they can manage the parties' costs budgets, control the timetable, limit expert evidence and impose sanctions on parties who flout the rules or court orders. Litigators have grown accustomed to robust judges exercising these wide powers to ensure proceedings are conducted justly and at proportionate cost. But there are limits to these judicial powers: judges cannot, for example, join in the cross-examination of witnesses without risking actual or perceived unfairness.

Court of Appeal decision on judicial intervention

In Shaw v. Grouby and another [2017] EWCA Civ 233 (6 April 2017) (Bailii), the defendants appealed a County Court decision on property law and rights of way issues, alleging that the judge's interventionist conduct had made a fair trial impossible. There was no allegation of bias but the defendants claimed that the judge's excessive interventions during the examination of both witnesses of fact and the expert witnesses had turned the trial into an inquisitorial rather than an adversarial process.

The allegations of procedural unfairness were supported by evidence such as the court transcript which showed that the judge had made constant interjections; had all but taken over the cross-examination of the defendants (whose behaviour he clearly disapproved of); and had even answered some of the questions put by counsel himself.  The defendants claimed they were deprived of the opportunity to put forward their case properly.

Judges should be impartial and neutral

The Court of Appeal considered the decisions in Southwark LBC v. Kofi-Adu [2006] EWCA Civ 281 and Jones v. National Coal Board [1957] 2 QB 55, which give guidance on what can amount to procedural unfairness. A first instance judge has wide but not unlimited discretion as to how proceedings are conducted. The priority – under the overriding objective set out in CPR 1.1 – is to deal with cases justly and at proportionate cost – but the process must be subservient to justice. Our adversarial system requires the judge to be impartial and neutral and "… to hear and determine the issues raised by the parties, not to conduct an investigation or examination on behalf of society at large".

While judges can now be more proactive and interventionist than those who heard the Jones case fifty years ago, interventions by the judge in the course of oral evidence (as opposed to interventions during counsel's submissions) carry risks. Interrogating witnesses at length can cloud a judge's "vision and judgment to the point where he [becomes] unable to subject the oral evidence to proper scrutiny and evaluation". "The greater the frequency of the interventions, the greater the risk; and where the interventions take the form of lengthy interrogation of the witnesses, the risk becomes a serious one."

The risk however does not depend on what the objective observer might think but rather whether the questioning impairs the judge's judgement and makes the trial unfair. In the Shaw case, the defendants challenged the judge's conduct and alleged that his questions and interventions during the factual and the expert evidence "amounted to his entering the arena so as to throw into doubt his objectivity and impartiality and made a fair trial impossible".

Excessive interventions in this case – but they did not affect the outcome

The Court of Appeal agreed with the defendants that the judge's interventions had been excessive. While accepting that the judge was always courteous – apologising regularly for his self-confessed "over-eager desire to get to grips with the case", he should nonetheless have curbed his enthusiasm and waited until counsel had completed cross-examination before asking the witnesses for clarification.

That said, the court concluded that:

• there had been a fair trial and a proper judicial determination of the main issues and the judge's ultimate decision was correct;
• the judge's decision had not depended on any findings of fact or concessions by the experts which could be said to have resulted from the judge's conduct of the trial;
• the judge's disapproval of the defendants' conduct, as evidenced in some of his interventions, related to a side issue and had no bearing on what he had to decide;
• while the interventions were frustrating for the defendants and their counsel, it did not lead to unfairness. The defendants' counsel had not been forced to leave out any line of questions to the witness. Nor was there any evidence in the transcripts that the judge had bullied the expert witnesses: his prolonged periods of questioning were to be expected nowadays in the age of "hot-tubbing", although it obviously has its limits.

Maybe we should not be surprised if judicial over-enthusiasm, when navigating the sometimes fine line between procedural and evidential matters, occasionally results in excessive intervention. We're all human after all. At least our legal system has a safety net for those rare cases in which a judge's intervention oversteps the mark and leads to unfairness. Had the judge's treatment of the witnesses displayed a hostility which gave an impression of bias or a complete lack of objectivity (as in Kofi-Adu), the Court of Appeal would have had little option but to order a re-trial.

While the Court of Appeal did not want to be too critical of the judge's conduct "in an environment where active trial management and a measure of judicial  interventionism" are acknowledged as appropriate case management tools, the judgment ends with the hope that judges in future "will temper eagerness with restraint", because judicial interruptions during cross-examination can "so often do more harm than good".

Key points

• Judicial case management powers under the CPR relate to the conduct of the proceedings. The CPR do not empower judges to collate evidence or cross-examine witnesses of fact or experts.
• Judges can seek clarification of the evidence from witnesses but this is best done after cross-examination has finished.
• Witnesses should not feel like they are being cross-examined simultaneously by opposing counsel and the judge – the often robust nature of cross-examination means that a party cross-examined by the judge could easily conclude the judge is hostile to the case.
• In our adversarial system, judges must be and be seen to be neutral and independent in carrying out their assessment of the parties' legal arguments and their evidence in support.
• In the event of perceived excessive intervention, the test to apply is whether the judge became so involved in the examination of the witnesses that he either made it impossible for counsel properly to conduct their clients' case or lost the ability to reach balanced and objective conclusions on the evidence he heard.
• Judges must exercise "judicial self-restraint" and remember that however strongly they feel about a party's behaviour, parties "must leave the trial process feeling that they have had a fair hearing and that their evidence was heard and understood".

This article was co-authored by Akin Akinbode and Tracey Summerell.