All Guides(39 guides)
What Is an Expert Witness?
The legal definition, duties, and procedural frameworks governing expert witness evidence in England and Wales. Covers The Ikarian Reefer duties, CrimPR Rule 19, CPR Part 35, and FPR Part 25.
Do I Need an Expert Witness?
A practical decision guide for solicitors on when expert evidence is required, which discipline to instruct, how court permission works, and how to obtain LAA funding.
Expert Witness vs Professional Witness
The legal distinction between expert witnesses and professional witnesses. Covers overriding duty, CrimPR Rule 19 compliance, independence requirements, and when each type is required.
How to Choose an Expert Witness
Seven steps to selecting the right expert witness — discipline matching, credential verification, CrimPR Rule 19 compliance, report quality assessment, and letter of instruction guidance.
Psychology vs Psychiatry Expert Witness
The clinical and legal distinctions between psychologists and psychiatrists. Covers which discipline addresses fitness to plead, diminished responsibility, PTSD, autism, and risk assessment.
CrimPR Rule 19 — Expert Witness Duties
A complete compliance guide to Criminal Procedure Rules 2020 Rule 19. Covers the overriding duty to the court, mandatory report elements under Rule 19.4, and the written declaration requirement.
The Ikarian Reefer Principles
The seven duties of an expert witness set out in The Ikarian Reefer [1993] 2 Lloyd's Rep 68. Explains how the principles are codified in CrimPR Rule 19, CPR Part 35, and FPR Part 25.
FPR Part 25 — Expert Evidence in Family Proceedings
How Family Procedure Rules 2010 Part 25 governs expert evidence in family proceedings. Covers court permission requirements, Practice Direction 25B, the 26-week timetable, and how FPR Part 25 differs from CrimPR Rule 19.
Expert Witness Immunity & Privilege
What changed after Jones v Kaney [2011] UKSC 13. Covers the abolition of expert witness immunity, what protection remains, litigation privilege, and the practical implications for experts and instructing solicitors.
Expert Witness Report Writing
What an expert witness report must contain under CrimPR Rule 19.4, CPR Part 35, and FPR Part 25. Covers the 9 mandatory elements, the written declaration, joint statements, and a solicitor's pre-service checklist.
Prior Authority & LAA Funding Guide
How to apply for LAA prior authority on Form CRM4, current codified rates by discipline, when prior authority is required, and how to handle retrospective applications.
Istanbul Protocol & Asylum Assessments
How the Istanbul Protocol (UN Manual on Effective Investigation of Torture) is applied in UK asylum and immigration proceedings. Covers the assessment framework, expert disciplines, and the Adults at Risk policy.
Hair Strand Testing in Family Court
How hair strand testing is used in family proceedings to assess chronic alcohol and drug use. Covers the science, accreditation standards, interpretation of results, and how courts treat the evidence.
Cell Site Analysis Expert Witness
How cell site analysis evidence is used in criminal proceedings. Covers the methodology, limitations, the R v Plunkett guidelines, and what instructing solicitors need to know about challenging cell site evidence.
Drug & Alcohol Testing Methods Explained
A guide to the main drug and alcohol testing methods used in family proceedings and criminal cases — urine, blood, hair strand, and breath testing. Covers detection windows, accreditation, and how courts assess the evidence.
Drug-Driving Defence Expert Evidence
How forensic toxicologists and pharmacologists provide expert evidence in drug-driving prosecutions under the Road Traffic Act 1988 s.5A, including statutory limits, back-calculation, and medical defences.
Risk Assessment Expert Evidence
An examination of structured professional judgement tools (HCR-20, OASys, RSVP, SAVRY) used by expert witnesses in dangerousness hearings, MAPPA reviews, and family court risk assessments.
PTSD in Legal Proceedings
How PTSD affects asylum claims, criminal defence, and family proceedings. Covers ICD-11 criteria, Istanbul Protocol, PCL-5, CAPS-5, the Adults at Risk policy, and expert discipline selection.
Fitness to Plead Assessments
How fitness to plead is assessed under the Pritchard criteria, which expert discipline conducts the assessment, what the report must contain, and how the court determines the issue.
ADHD & Autism in Criminal Proceedings
How ADHD and autism spectrum disorder affect fitness to plead, diminished responsibility, sentencing mitigation, and MHA disposals. Covers assessment tools, discipline selection, and LAA funding.
Forensic Toxicology Expert Witness
The role of the forensic toxicologist in criminal proceedings — drug driving, cause of death, post-mortem redistribution, and back-calculation. Covers methodology, key cases, and how to instruct a forensic toxicology expert.
Brain Injury Expert Witness
How brain injury evidence is used in criminal proceedings and family law. Covers acquired brain injury, traumatic brain injury, neuropsychological assessment, and the impact of frontal lobe damage on culpability and risk.
Diminished Responsibility Expert Witness
How psychiatric expert evidence supports a diminished responsibility defence under s.2 Homicide Act 1957 (as amended). Covers the statutory criteria, the role of the expert, key cases, and practical guidance for instructing solicitors.
Mental Health Act Assessments in Criminal Proceedings
How Mental Health Act assessments are used in criminal proceedings — s.35 remand for reports, s.36 remand for treatment, s.37 Hospital Orders, and s.41 Restriction Orders.
Challenging Expert Evidence in Criminal Proceedings
How defence solicitors can challenge prosecution expert evidence in criminal proceedings. Covers admissibility, reliability, joint expert discussions, advocacy bias, and instructing a counter-expert.
Sentencing Mitigation Expert Witness
How psychiatric and psychological expert witnesses support sentencing mitigation in criminal proceedings. Covers pre-sentence reports, dangerousness assessments, mental health treatment requirements, and neurodevelopmental conditions.
Letter of Instruction to Expert Witness
What a compliant letter of instruction must contain under CrimPR Rule 19, CPR Part 35, and FPR Part 25. Covers mandatory disclosures, how to agree the letter with opposing parties, and common drafting errors that delay proceedings.
Joint Expert Statements — CPR Part 35
How joint expert discussions and statements of agreement and disagreement work under CPR Part 35, CrimPR Rule 19.6, and FPR Part 25. Covers the without-prejudice rule, the legal effect of agreed statements, and how courts use them at trial.
Role of Expert Witness in Family Court
How expert witnesses are instructed, what they must produce, and how courts use their evidence in Children Act proceedings. Covers FPR Part 25 permission requirements, the overriding duty to the court, and the difference between single joint experts and separately instructed experts.
Parenting Capacity Assessment in Family Court
What parenting capacity assessments involve, how they are commissioned under FPR Part 25, the assessment frameworks used by psychologists and psychiatrists, and how courts weigh the findings in care and adoption proceedings.
Non-Accidental Injury Expert Evidence
How expert witnesses assess and present evidence of non-accidental injury in family proceedings, including biomechanical analysis, differential diagnoses, and the approach required following Re R and the Lucas direction on lies.
Domestic Abuse & Coercive Control Assessments
The role of psychological expert witnesses in assessing domestic abuse, coercive control, and PTSD in family proceedings. Covers the Domestic Abuse Act 2021, Practice Direction 12J, and the use of DASH risk assessments.
Assessing Litigation Capacity in Family Court
When and how litigation capacity is assessed in family proceedings, the legal test under the Mental Capacity Act 2005, the role of the Official Solicitor, and what a capacity assessment report must contain to satisfy the court.
Vulnerability Assessment in Immigration Proceedings
How psychological and psychiatric expert witnesses assess vulnerability in asylum and immigration proceedings, including the Home Office Adults at Risk policy, Rule 35 reports, and the evidential weight of expert vulnerability evidence.
Age Assessment in Immigration Proceedings
The legal framework for age assessments in immigration proceedings following R (BF) v Hereford, the Merton-compliant assessment standard, the role of expert witnesses, and how disputed age affects asylum claims and detention decisions.
Modern Slavery & Trafficking Expert Evidence
How expert witnesses support criminal defence and immigration cases involving modern slavery and trafficking, including the National Referral Mechanism, the Modern Slavery Act 2015 s.45 defence, and psychological trauma assessments.
What to Expect: Psychological Assessment for Legal Proceedings
A step-by-step guide for solicitors and defendants on what happens during a psychological assessment for court, from initial instruction through to report delivery and cross-examination.
What to Expect: Psychiatric Assessment for Legal Proceedings
A practical guide to the psychiatric assessment process in criminal, family, and immigration proceedings, covering the Mental State Examination, diagnostic formulation, and the expert's duty to the court.
Expert Witness Court Attendance: What to Expect
A comprehensive guide to giving oral evidence as an expert witness in Crown Court, Family Court, and the Upper Tribunal, covering examination-in-chief, cross-examination, and the hot-tubbing procedure.
Expert Witness Fees & LAA Codified Rates
Current LAA codified rates by discipline, how fixed fees and hourly rates are structured, and what to include in a fee agreement before instruction. Covers psychology, psychiatry, neurology, forensic, drug & alcohol, and CCTV & digital forensics.
Browse by Expert Discipline
Each discipline page sets out the types of cases covered, the assessments available, the regulatory framework, and the LAA codified rates.
Psychology
Cognitive assessment, PTSD, autism, learning disability, fitness to plead
Psychiatry
Mental disorder, diminished responsibility, risk assessment, s.37/41 reports
Neurology
Acquired brain injury, epilepsy, neurological basis of behaviour, capacity
Forensic
DNA, fingerprints, ballistics, trace evidence, document examination
Drug & Alcohol
Toxicology, hair strand testing, substance dependency, drug-driving
CCTV & Digital
CCTV enhancement, digital device examination, metadata analysis
About These Guides
Every guide on this page is written for practising solicitors and barristers in England and Wales. The content is grounded in the current procedural rules — Criminal Procedure Rules 2020 (SI 2020/759), Civil Procedure Rules Part 35, and Family Procedure Rules Part 25 — and updated to reflect current LAA Standard Civil Contract rates.
Expert Witness UK is a fully managed expert witness agency. All experts on our panel are pre-vetted, hold current regulatory registration with the GMC, HCPC, or BPS, and produce reports that comply with the applicable procedural framework. We respond promptly to every instruction.
These guides are practical reference materials for legal professionals who instruct expert witnesses in criminal, immigration, and family proceedings. For case-specific guidance, contact our admin team directly.