Single Joint Experts in Psychiatry: When Are They Appropriate?

Introduction

A Single Joint Expert (SJE) can be an efficient way to obtain psychiatric expert evidence, particularly where proportionality is important and the issues can be addressed by a single, independent opinion. Used well, an SJE avoids unnecessary duplication, limits cost, and can help narrow issues in dispute. Used poorly, it can create delay, add expense through avoidable addenda, and produce a report that fails to address the questions the court actually needs answered.

This guidance explains what an SJE is, when an SJE in psychiatry is likely to be suitable, when separate experts may be preferable, and the practical steps solicitors can take to obtain clear, focused, and procedurally compliant psychiatric evidence.

This page is provided for general informational purposes and does not constitute legal advice.

What Is a Single Joint Expert?

A Single Joint Expert is one expert instructed by two or more parties to provide expert evidence on defined issues. In the psychiatric context, the SJE’s role is to assist the court by offering independent clinical opinion within their expertise—based on the available records, the assessment, and transparent reasoning.

An SJE is not “your” expert and not a vehicle for advocacy. The expert’s overriding duty is to the court, and the report should reflect neutrality, independence, and clear explanation of clinical findings and how those findings support the conclusions.

Why SJEs Are Used (and When They Work Best)

Courts encourage the use of an SJE where it is a proportionate way to obtain reliable expert evidence. In many cases, a single, carefully instructed psychiatrist can provide everything required: diagnosis (where appropriate), severity, functional impact, treatment needs, and prognosis—alongside a reasoned discussion of causation where the evidence base allows.

The SJE route tends to work best when the issues are capable of being framed clearly, the disclosure is reasonably complete, and the assessment can proceed on a stable factual foundation rather than shifting accounts or late-emerging records.

When an SJE May Be Unsuitable (or Higher Risk)

An SJE is not the right approach in every psychiatric dispute. Certain fact patterns make the instruction materially harder to manage and increase the risk of delay, addenda, or disagreement about the scope of the expert’s task.

Where these features are present, parties should consider whether the court will be better assisted by separate experts (or by a different expert strategy), rather than expecting a single report to carry the full evidential burden in a contested landscape.

Advantages and Trade-Offs

Potential advantages

• Reduced duplication of professional time, and often lower overall cost.
• A single assessment process for the individual, which can be less burdensome.
• A single coherent clinical framework that may help narrow issues and support settlement discussions.
• A report that is less vulnerable to “expert versus expert” disagreements on routine issues.

Practical trade-offs

• Less control over emphasis and presentation: the report is independent and may not align with either party’s preferred narrative.
• If the joint instruction is poorly framed, both parties inherit the consequences.
• Disagreements about scope or late questions can introduce delay and additional cost.
• If significant new material emerges later, addenda may be required and the timetable can slip.

How to Instruct an SJE Well

The strongest SJE reports are the product of strong, disciplined instructions. Clarity at the outset reduces later disagreement and minimises the need for addenda.

1) Agree scope early, and keep it tight

Define the purpose of the report, the issues to be addressed, and whether the opinion is primarily retrospective, contemporaneous, or both. Where multiple issues arise, separate them and prioritise the questions that are genuinely in dispute.

2) Provide complete and organised disclosure

Psychiatric opinion is only as robust as the evidence base. Where relevant, provide core clinical records (for example GP, mental health services, therapy notes where disclosed, and medication history), alongside relevant occupational, educational, and case documents where they materially inform function, chronology, or causation. If key records are outstanding, flag this early and agree whether the assessment should proceed or be deferred.

3) Clarify the procedural context and timetable

Confirm the applicable procedural framework, key dates, and whether written questions and/or an addendum are anticipated. A realistic timetable allows time for records review, assessment, careful drafting, and quality assurance.

4) Control scope creep and agree how additional work is handled

The most common SJE derailment is gradual expansion of the instruction after the assessment has taken place. Agree a simple process for additional questions and supplementary work, including confirmation of fees before work is undertaken wherever practicable.

What to Expect in Practice

While each case differs, the SJE process is usually most efficient when it is treated as a structured case-management exercise rather than an informal referral.

1. Parties identify a suitable psychiatrist and confirm availability.
2. A joint letter of instruction is finalised and disclosure is collated in an organised bundle.
3. The expert confirms suitability, scope, conflicts, and timetable.
4. Assessment is arranged and completed (with clear arrangements for non-attendance or late documentation).
5. The report is prepared, quality checked, and served in line with the agreed timetable.
6. Written questions and any agreed addendum work are handled promptly and transparently.

Fees, Billing, and Cost Management

SJE fees are typically based on professional time and the scope of the instruction, including records review, assessment, and report preparation. Arrangements for invoicing and apportionment vary by case and should be clarified at the outset. VAT is charged where applicable in accordance with current law.

Additional work may arise after service (for example written questions, addenda, conferences, or attendance). Where practicable, fees for additional work should be discussed and agreed before the work is undertaken.

See our Fees & Payment page for further detail on our billing approach and payment terms.

Selecting the Right Psychiatrist

The quality of an SJE report depends heavily on expert suitability. Parties should consider not only qualifications but also current clinical practice, relevant subspecialty experience, medico-legal familiarity, and the expert’s ability to explain reasoning clearly in a form that assists the court.

Practical factors matter too: availability within the court timetable, comfort with written questions and supplementary work, and transparent processes for disclosure and scheduling.

Common Pitfalls (and How to Avoid Them)

• Vague joint questions: agree focused, numbered questions tied to the real issues in dispute.
• Late disclosure: collate key records early, and be clear about what is outstanding.
• Scope creep: agree how additional questions are proposed and costed.
• Unrealistic timetables: allow time for records review, assessment, drafting, and any post-report questions.

For broader instruction guidance, see Common Pitfalls and How to Avoid Them.

Conclusion

A Single Joint Expert can be an excellent choice in psychiatric cases where the issues can be framed clearly and addressed proportionately by one independent clinician. The approach is most effective when parties invest effort upfront: agreeing scope, providing complete disclosure, and managing the instruction as a structured process.

Where the factual narrative is heavily contested, the clinical issues are particularly complex, or multiple disciplines are required, parties should consider whether a different expert strategy is more likely to assist the court.