General
As a forensic scientist, your overriding duty is to the court and to the administration of justice.
All members should perform their professional activities with honesty, integrity, objectivity and impartiality. UKIAFT members should not knowingly misrepresent their professional or academic/educational experience including the UKIAFT membership. Membership of UKIAFT should not be regarded as a qualification.
Any personal, business and/or financial interest that could be perceived as a conflict of interest in any casework they are asked to carry out must be declared at the earliest possibility. The conflicts of interest, perceived or otherwise, and threats to impartiality may include
- having the perception of being coerced, or being coerced, openly or secretively;
- being the sole reviewer of critical findings;
- being involved with activities that could be perceived as witness coaching or being coached, rather than training or familiarisation;
- being over-familiar with or trusting another person instead of relying on objective evidence;
- having organisational and management structures that could be perceived to reward, encourage or support bias;
- having a close/significant personal or financial relationship with a party likely to be affected by the outcome;
- having a close/significant personal or financial relationship with any person acting as an expert witness in the case; or
- acting in self-interest.
You should inform a suitable person within your organisation and/or the Forensic Science Regulator if you have good grounds for believing there is a situation that may result in a miscarriage of justice.
Interpretation and competence
Scientists working in the forensic field are often asked to offer an opinion or an interpretation, in order to assist in the understanding of the results they have produced as part of the analysis or examination of forensic exhibits.
When expert advice or opinion is given, it is essential not to exceed the limits of individual competence or knowledge and should be backed up where possible with scientific evidence. Testimony to the criminal justice system should be given impartially with any limitations made clear to the court. It is essential for the court to be able to distinguish clearly between fact and scientific opinion.
Reasonable steps should be made to maintain and develop competence by taking account of material research and developments within the relevant field (continuous professional development). For example, being up to date with the latest scientific journals, attending meetings/conferences, refresher training, workshops etc.
Scientists should maintain and keep readily available appropriate records of education (academic and/or professional qualifications), training (courses attended etc), skills and experience in sufficient detail to provide evidence of proper training and formal assessment (dates on which competence and authorisation were confirmed etc).
Toxicologists who provide expert evidence should ensure they have a sufficient level of experience, knowledge and where appropriate, qualifications, relevant to toxicology, to give credibility to the reliability of the work undertaken and the conclusions drawn. They shall also ensure that they are able to explain their methodology and reasoning, both in writing and orally, concisely in a way that is comprehensible to a lay person and not misleading.
If they feel they are not being given the appropriate training this should be raised with an appropriate member of management. The toxicologist must be confident that their level of training is up to standard and they can defend their opinions and decisions made on the case in a court of law.
Scientists should be able to demonstrate that the principles, techniques and assumptions they have relied on are valid and comply with relevant criminal procedure rules.
Any database that has been relied on should be sufficient in size and quality to justify the nature and breadth of inferences drawn from it. Any inferences should be logically sound and alternative hypotheses and propositions should be properly considered. Methodology, assumptions and reasoning should always be considered by other scientists during peer review where possible and should be regarded as sound, or where challenged, the concerns should be satisfactorily addressed. They should also consider what impact the uncertainty of measurement associated with the application of a given method could have on any conclusions.
Conclusions and reasoning should be based on case experience and published scientific literature. When referencing a body of specialised literature relating to a field of expertise, you should consider the extent to which this supports or undermines your methodology and reasoning.
Casework
Casework should be carried out in accordance with the UKIAFT Guidelines and to the required level of accreditation, for example BS EN ISO/IEC 17025:2017.
The integrity and continuity of items should be ensured and maintained in accordance with UKIAFT Guidelines3.
Where applicable it is expected that the expert, in assessing the results obtained, would consider the relevant hypotheses that could explain their findings prior to presenting relevant hypotheses as propositions to the case.
Scientists should be prepared to review casework if any new information or developments are identified that would significantly impact on the findings and may change the original opinion.
Where possible it also recommended that all casework presented to court is peer-reviewed by a second appropriately qualified person. The review shall establish from the case notes and discussion with the practitioner that the work carried out is: appropriate to the requirements of the case, is fully documented in the case notes with appropriate checks on critical findings, calculations and data transfers in compliance with the provider’s documented policies and procedures, and consistent with the contents of the report or statement.
The case records should indicate that a review has been carried out, by whom and when. The checks and reviews shall be recorded as entries against each finding or on a summary of findings or on a report, as appropriate. If the checker/reviewer disagrees on any point and the matter cannot be resolved, the reason(s) for the disagreement and any action taken as a result should be recorded.
Confidentiality and disclosure
Confidentiality must be preserved unless the law obliges, a court/tribunal orders, or a customer explicitly authorises disclosure. Privacy and dignity of individuals involved in casework (living or deceased) should be respected at all times.
Scientists must be aware and support the disclosure process and provide access to the defence. For England and Wales, further guidance is set out in the ACPO/CPS Guidance Booklet for Experts, Disclosure: Experts’ Evidence Case Management and Unused Material.
Research and development
Research and development is of particular importance in the field of toxiciology, as is the presentation and publication of these findings in relevant scientific journals, scientific meetings, workshops etc. However, care must be taken to ensure confidentiality at all times, especially that relating to real cases and on-going research. The correct and most appropriate permission for such publications must be obtained from the relevant authorites prior to any findings being made public and authors should be aware of laws governing copyright. All published work should be based on clear and accurate scientific data and should not be manipulated, or parts omitted, in order to bias a particular outcome or interpretation.
References
- Forensic Science Regulator : Code of Practice. Version 2.0 Published May 2025.
- Forensic Science Regulator : Recommendations of the editorial group on the Code of Conduct. QSSG 2010.12.16-2. Published 10 February 2011.
- Simon P Elliott, Duncan WS Stephen and Sue Paterson. The United Kingdom and Ireland Association of Forensic Toxicologists: forensic toxicology laboratory guidelines (2018). Science & Justice, Vol.58(5), 2018, p335-345.
