ARCHIVED: Note: • this Practice Note provides guidance on provisions which came into force on 1 April 2013 • this Practice Note only addresses the amendments to CPR 35.4. For guidance on the introduction of concurrent expert evidence (also introduced under the Jackson Reforms) or on expert evidence generally, see: Hot-tubbing (Concurrent expert evidence) and Experts' meetings and joint statements respectively • you should also have regard to all relevant provisions set out in any applicable court guide. See: Court guides and other guidance NOTE: This Practice Note provides a summary of the amendment to CPR 35.4 introduced on 1 April 2014. It does not address developments since that date and is, therefore, not maintained. Lord Justice Jackson's recommendations—effective case management Lord Justice Jackson identified expert evidence as one of the areas in which the cost of litigation could potentially be significantly reduced. He observed that if expert reports ‘are longer than they need to be, or address (at length) matters that are irrelevant or at best peripheral, or which ought not

This Practice Note looks at what to take into account when considering expert evidence and the need for it. It also provides guidance on the importance of the relevant expertise of experts and proposed experts, the sorts of issues and disputes where expert evidence may be required including issues involving foreign law and researching and considering other forms of expert evidence. This Practice Note provides guidance on the interpretation and application of the relevant provisions of the CPR. Depending on the court in which your matter is proceeding, you may also need to be mindful of additional provisions—see: Court specific guidance. This Practice Note should also be read in conjunction with our Practice Notes: • Applying for permission to adduce expert evidence • Duties of an expert When instructing experts you are expected to have regard to: • all relevant CPR Rules and Practice Directions • the Guidance for the instruction of experts in civil claims ‘the Guidance‘. Note: on 1 December 2014, the Guidance replaced the ‘Protocol for the Instruction of Experts to give Evidence

This Practice Note identifies and summarises significant cases concerning the responsibilities of legal advisers in working with expert witnesses asked to prepare and to give evidence in a civil court and the duties of expert witnesses themselves. Based on these cases, it outlines matters that should either be avoided or embraced by practitioners when selecting, instructing and engaging with expert witnesses. Admissibility of opinion evidence The admissibility of opinion evidence given by witnesses with expertise in the relevant area of expertise is considered in the Supreme Court’s decision of Kennedy v Cordia (Services). The court identified ‘four considerations which govern the admissibility of skilled evidence’ (the term for expert evidence in civil procedure in Scotland where the case originated) as whether: •  the proposed skilled evidence will assist the court in its task • the witness has the necessary knowledge and experience • the witness is impartial in his or her presentation and assessment of the evidence • there is a reliable body of knowledge or experience to underpin the expert's evidence These

The European Medicines Agency and the Heads of Medicines Agencies have published an expert review report on the utility of mobile health (mHealth) data for regulatory decision-making. It found that mHealth data was particularly useful to the design of applicant studies by informing eligibility criteria and the choice of study measurements meaningful for patients, and can provide valuable insights into disease spread and progression through wearable sensors measuring patient symptoms and health apps tracking the spatial prevalence of disease. In addition, mHealth data was identified as useful in post-authorisation monitoring by supporting adverse drug reaction characterisation and signal detection, and in assessing the effectiveness of medicines by measuring biomarkers associated with disease and recovery. The expert review also identified various challenges, namely with regards to data protection, accessibility, and correct use by patients, and set out seven recommendations for future actions.

This Practice Note provides guidance on the interpretation and application of the relevant provisions of the CPR. You may also need to refer to additional provisions in court guides—see: Court specific guidance below. Preparation of expert report This Practice Note proceeds on the basis that you have obtained permission to adduce expert evidence and your evidence is not to be prepared or given by a single joint expert. For guidance on seeking permission to adduce expert evidence, see Practice Note: Applying for permission to adduce expert evidence and see for guidance on Single joint experts. Expert witnesses and those instructing them are expected to have regard to: • all relevant CPR Rules and Practice Directions, in particular CPR 35 and CPR PD 35 • the Guidance for the instruction of experts in civil claims (the Guidance) • Practice Direction Pre-Action Conduct and Protocols, para 7 For guidance on the expert's duties, see Practice Note: Duties of an expert. Model form expert reports The Guidance directs experts to model expert reports made available by bodies such as: • the

This Practice Note looks at the importance of the experts’ testimony and credibility at trial and, accordingly, the weight that may be given to expert evidence. It considers the court’s reasons for preferring the evidence of one expert over another, when a court may choose between expert evidence and its own assessment, what happens when an expert is not called to give evidence or cross-examined including the weight that can be given to unchallenged evidence and practical tips for expert testimony. Expert witnesses and those instructing them are expected to have regard to: • relevant CPR rules and Practice Directions • the Guidance for the instruction of experts in civil claims (the Guidance). On 1 December 2014, the Guidance replaced the ‘Protocol for the Instruction of Experts to give Evidence in Civil Claims’ which had been annexed to CPR PD 35 • Practice Direction Pre-Action Conduct and Protocols, para 7 • court specific guidance found in court guides Attendance of experts at court Expert evidence is to be given in a written report, unless the court directs otherwise

Expert witness disclosure is the process by which a party identifies its expert witnesses and provides their evidence to other parties and the court within prescribed time limits. It typically includes the expert’s name, qualifications, instructions (to the extent disclosable), reports, joint statements and any supplemental opinions. In England and Wales and Northern Ireland, the concept arises mainly under civil procedure rules on expert evidence and disclosure, and is shaped by case law on independence, privilege and the proper scope of instructions. In Scotland and Ireland, similar duties arise through court rules and practice directions, although terminology and procedural steps may differ. Expert witness disclosure is crucial for case management, enabling opposing parties to test methodology, commission responsive reports and prepare cross-examination. It engages issues of legal professional privilege, confidentiality, proportionality and compliance with timetables. Late or inadequate disclosure can lead to exclusion of expert evidence, adverse costs orders or adjournments. Across the UK and Ireland, courts emphasise that disclosure must support the overriding objective or equivalent, ensure transparency in expert reasoning and avoid trial by ambush, while preserving core privileged communications where appropriate.

Mealey’s: Deploying expert witnesses in international and domestic arbitration in the US differs significantly from traditional courtroom practice. Expert testimony often plays a decisive role. Yet arbitrators and judges are rarely specialists in the scientific, financial or technical disciplines presented to them. How, then, do decision-makers assess competing experts and how reliable is that assessment? Three techniques—tribunal tutorials, written direct testimony and witness conferencing—have become expected in complex commercial arbitrations. Arbitrators increasingly believe that procedural mechanisms such as ‘hot-tubbing’ (concurrent expert evidence), tribunal-appointed experts and written expert conferencing improve comprehension and reliability. Understanding each technique and knowing when to use it is now a core skill for arbitration practitioners.

This Practice Note considers the framework within which expert witness evidence is presented in arbitration proceedings. The role of the expert witness in arbitration proceedings is broadly the same as that of the expert in civil litigation proceedings. Whether appointed by the parties or, less commonly, by the tribunal, the expert is required to give their independent expert opinion on the issue(s) referred to them, based on the facts presented to them, and applying their own expertise and experience. The parties and the tribunal may question or challenge the expert, and the tribunal must decide which expert’s evidence it prefers or, in the case of a single expert, whether to accept their evidence. While an arbitrator may have been selected for their relevant experience or expertise, typically this is to ensure the arbitrator has an understanding of the issues in the dispute and is not intended to put the arbitrator in the role of an expert giving and relying on their own opinion in making their award. In international arbitration in particular, arbitrators are very often lawyers

This Practice Note explains the distinction between expert witnesses and expert advisers, the principal differences between the two roles, the benefits and disadvantages of using an expert adviser and what needs to be considered if later instructing an expert adviser to act as expert witness. It also considers what an assessor is and their role within some proceedings. This Practice Note provides guidance on aspects of the court rules. Depending on the court in which your matter is proceeding, you may also need to take note of guidance in the various court guides—see the section: Court specific guidance below. Expert witnesses, and those instructing them, are expected to have regard to: • all relevant CPR Rules and Practice Directions • the Guidance for the instruction of experts in civil claims ('the Guidance') which replaced the 'Protocol for the Instruction of Experts to give Evidence in Civil Claims • Practice Direction Pre-Action Conduct and Protocols, para 7 • any relevant provisions depending on the track and/or the court in which your matter is proceeding—see Practice

Law360: The government should form a commission to secure long-term commitments and stability for pensions policy as the country gears up for potential political upheaval in 2023.

Law360, Expert analysis: The Financial Conduct Authority (FCA) has failed to set out how its rules meet government requirements on regulating artificial intelligence (AI) and is moving toward reliance on companies to self-report, putting it at risk of deferring excessively to the sector it regulates, legal experts say.