Split trials, preliminary issue trials and clear bright lines

The terms ‘split trial’ and ‘trial of preliminary issues’ are often used interchangeably. They do however play distinct roles: this article reviews the difference between them and provides a summary of the factors to be taken into account by a court when considering whether to make such an order.  

In Jinxin Inc v Aser Media Pte Ltd [2022] EWHC 2431 (comm) the court observed that although they often amount to the same thing, the archetypical characteristics of each are:

• Preliminary issue trial: one which requires the determination of one or a few issues (often an issue of law), which occupies the Court for a short time and whose outcome has the real potential to save a potentially longer trial. (The Kings Bench Guide identifies (at para 10.31) that a trial of a preliminary issue may be appropriate where the decision of one issue may enable the parties to settle the remainder of the dispute, even if not being decisive of the claim as a whole).
• Split trial: may involve all of the issues being determined at two or more separate hearings, each concerned with a substantial number of issues both of law and fact. Very often the first trial need not make any assumptions of fact.

Whether to order a trial of a preliminary issue or a split trial is a case management decision: the Court’s power is derived from CPR 3.1(2): “Except where these Rules provide otherwise, the court may…(j) direct a separate trial of any issue; (k) decide the order in which issues are to be tried”. That broad case management discretion is to be exercised in accordance with the overriding objective (CPR 1.1(1): to enable the court to deal with cases justly and at proportionate cost). The CPR provide no other test or guidance, but in Soroka v Payne Hicks Beach (A Firm) [2025] EWHC 602 (Ch) Master Kaye’s judgment reviewed previous cases and summarised the guidance as to when to order a trial of preliminary issue. This was a first instance decision refusing to order a split trial in a professional negligence claim. The claimant wanted a preliminary trial on the issue of duty of care and breach, with a trial of causation and loss thereafter.

Master Kaye noted that although the court’s case management discretion is to be exercised in accordance with the overriding objective, if there is not a sufficiently clear linebetween the issues, such an order may have the unintended consequence of increasing costs by creating satellite disputes. The starting point and often the end point is therefore whether there is a sufficiently ‘clear bright line’ between the issues to be determined at each stage such that in principle a split trial is possible. If the court is satisfied that in principle a split trial is possible then it must take a common-sense pragmatic approach and consider whether, in all the circumstances of the particular case, it is in the interests of justice to direct a split trial. Earlier judgments were not intended to provide a comprehensive or exhaustive list of factors.

In Steele v Steele[2001] CP Rep 106, Neuberger J identified a series of questions or considerations, now often treated as a checklist, when considering whether to order either preliminary issues or split trials:

1. Will the determination of the preliminary issue dispose of the case, or at least one aspect of the case?
   1. Could determination of the preliminary issue significantly cut down the cost and time involved in pre-trial preparation or in connection with the trial itself?
   1. If the preliminary issue is one of law, how much effort will be involved in identifying the relevant facts for the purpose of the preliminary issue?
   1. If the preliminary issue is an issue of law, to what extent is it to be determined on agreed facts?
   1. Where the facts are not agreed, to what extent does that impinge on the value of a preliminary issue?
   1. May the determination of a preliminary issue unreasonably fetter either or both parties or the court, in achieving a just result?
   1. To what extent is there a risk of the determination of the preliminary issue increasing costs and/or delaying the trial? The greater the delay caused by the preliminary issue and the greater the possibility of an increase in costs, the less desirable it is.
   1. To what extent may determination of the preliminary issue be irrelevant?
   1. To what extent is there a risk that the determination of a preliminary issue could lead to an application for the pleadings being amended to avoid the consequences of the determination?
   1. Taking into account all the previous points, is it just to order a preliminary issue trial?

With that non-exhaustive ‘checklist’ in mind, any application for a split trial etc must address the key issues of the opportunity to dispose of (some of) the claim; costs savings to be made; ease of identifying the issues and potential delay.

The importance of being able to identify the issues was emphasised also in McLoughlin v Grovers (A Firm) [2001] EWCA Civ 1743. Per Steel J:

“As Lord Scarman observed in Tilling v Whiteman [1980] AC 1 at p25: “Preliminary points of law are too often treacherous short cuts”. The dangers are all the greater where, as here, the preliminary issues are set in motion in a casual and unstructured way…(para 66) In my judgement, the right approach to preliminary issues should be as follows: (a) only issues which are decisive or potentially decisive should be identified; (b) the questions should usually be questions of law; (c) they should be decided on the basis of a schedule of agreed or assumed facts; (d) they should be triable without significant delay, making full allowance for the implications of a possible appeal; (e) any order should be made by the court following a case management conference.”

Any application for a trial of preliminary issues/split trial must therefore clearly set out which matters are to be determined at each trial.

In Soroka the Master also referred to Electrical Waste Recycling Group Ltd v Philips Electronics UK Ltd [2012] EWHC 38 (CH), an application for a split trial, with quantum of damages to be tried separately from all other issues. The court considered CPR 1.4(2): “Active case management includes…(i) dealing with as many aspects of the case as it can on the same occasion” and observed that the decision whether to split trials is essentially a pragmatic one, with various (sometimes competing) considerations. Those considerations were stated to include:

• Costs implications;
  • (Dis)advantages in terms of trial preparation and management;
  • Whether a split trial will impose unnecessary inconvenience and strain on witnesses who may be required in both trials;
  • Whether a single trial will lead to excessive complexity and diffusion of issues, or place an undue burden on the judge hearing the case;
  • Whether a split may cause particular prejudice to one or other of the parties (eg by delaying any ultimate award of compensation or damages);
  • Whether there are difficulties of defining an appropriate split, or whether a clean split is possible;
  • What weight is to be given to the risk of duplication, delay and the disadvantage of bifurcated appellate process;
  • What is perceived to offer the best course to ensure that the whole matter is adjudicated as fairly, quickly and efficiently as possible;
  • Whether a split trial would assist or discourage mediation;
  • Whether a split trial might actually increase costs.

In Electrical Waste the court highlighted that each case falls to be assessed by reference to its own facts, features and peculiarities and that experience has confirmed the importance of ensuring there be careful demarcation of the boundary between the two trials, in terms of the issues to be dealt with at each stage.

The checklist from Electrical Waste was adopted (and adapted) by the Court in Jinxin, where the Court observed:

“The fact remains that the decision to split what would otherwise be a single trial into more than one trial each dealing with defined issues is a step out of the norm, where in most cases there will be a single trial determining all of the issues arising in an action. Accordingly, there must be a real and substantial advantage if a split trial were ordered to take place. In Bindel v PinkNews Media Group Ltd [2021] EWHC 1868 (QB); [2021] 1 WLR 5497, Nicklin J said at para 33: “A case in which the court directs determination of a preliminary issue that will require resolution of disputed issues of fact, including disclosure, witness statements and cross-examination, must be regarded as an exception to the general rule, and one that requires careful consideration by the court and very clear justification.”

24. It is also salutary to recall the warning of Lord Neuberger, MR in Rosetti Marketing Ltd v Diamond Sofa Company Ltd [2012] EWCA Civ 1021; [2013] 1 All ER (Comm) 308, at para. 1 in connection with the proposal for trials of preliminary issues: “… It represents yet another cautionary tale about the dangers of preliminary issues. In particular, it demonstrates that (i) while often attractive prospectively, the siren song of agreeing or ordering preliminary issues should normally be resisted, (ii) if there are none the less to be preliminary issues, it is vital that the issues themselves, and the agreed facts or assumptions on which they are based, are simply, clearly and precisely formulated, and (iii) once formulated, the issues should be answered in a clear and precise way.”

…26. Unless a split trial can be justified as a means of resolving the disputed issues in action in accordance with the overriding objective with clear benefits over and above those of a single trial, the peril exists that a split trial will add considerably to the parties’ costs burden, will delay the conclusion of the action (with an unappealing drain on the Court’s resources) and/or will lead to unanticipated difficulties.”

Taken together, to comply with the guidance set out above, any application for a preliminary issue/split trial must:

• highlight the ‘clear bright line’ between the issues to be determined at each stage such that in principle a split trial is possible (per Soroka).
• address the various factors indicated as potentially relevant in Steele v Steele and Electrical Waste. 
• Provide an overview of the ‘common-sense pragmatic approach’. Is a split trial in the interests of justice having considered all the circumstances of the particular case? Is it consistent with the overriding objective and good case management?

About the Author

Linda Nelson was called in 2000, has a specialist personal injury and clinical negligence practice and is ranked in the Legal 500 and Chambers and Partners for her personal injury and travel law work. Linda regularly advises in international personal injury cases with cross-border issues, particularly those falling within the jurisdiction of the Admiralty Court. Her practice consists of the more substantial and complex cases, including RTA fraud, insurance and MIB issues, fatal accidents and catastrophic injuries, and she is well-versed in claims involving the international carriage conventions, the package holiday regulations, Merchant Shipping regulations, ship collisions and issues of jurisdiction, applicable law and limitation. She is a contributing author to Munkman on Employers’ Liability (writing the ‘Shipping and Workers on Ships’ chapter), Kemp and Kemp’s Personal Injury Law, Practice and Procedure (writing the Fatal Accidents and the Low Velocity Collision chapters) and she co-authored ‘Work Accidents at Sea’ (now in its third edition).