John Leach – Independent Drug Expert Witness
Areas of Expertise
-
Illicit drug trafficking and supply
-
Drug valuation and quantum reports
-
Drug Lines
-
County Lines
-
EncroChat, Sky ECC and other encrypted communications
-
Organised Crime Groups and criminal methodologies
-
Drug trafficking - importation/exportation
-
Cannabis cultivation
-
Interpretation of communications data
-
Proceeds of Crime Act matters
Professional Experience
John has worked within the field of law enforcement for over 35 years, investigating a range of criminality including Serious and Organised Crime within London’s Metropolitan Police Service.
He was a founder member of the Met’s original Dedicated Drug Expert Witness Unit within the Specialist Crime Department, where, up until his retirement in 2020, he assessed and completed expert reports in hundreds of drug trafficking investigations at all levels in the supply chain.
John rejoined the Met as a full-time, dedicated Drug Expert Witness in 2021 within the Violent Crime Task Force and was involved in training and quality assurance for new and existing drug experts, while continuing to complete hundreds of expert reports relating to a wide range of drug trafficking investigations.
During his exemplary service, he has written more drug expert reports than any other serving Met employee and, over the past 10 years, has provided expert opinion evidence in every permanent Crown Court in London.
Types of Instruction Accepted
-
Independent expert reports for criminal proceedings
-
Instructions from prosecution and defence teams
-
Review of existing prosecution or defence expert evidence
-
Drug valuation and quantum reports
-
Analysis and interpretation of communications & data
-
Drug dealer notes, ledgers and debtor lists
-
Case conferences with solicitors, counsel and investigators
-
Peer review and quality assurance of expert reports
-
Oral expert evidence in court
Legal Aid Agency funded cases are accepted, subject to the nature of the instruction and the required funding authority.
Independence and Professional Standards
John’s overriding duty as an expert witness is to assist the court. His opinions are independent, impartial and limited to matters within his expertise, regardless of which party provides the instruction.
Reports are prepared in accordance with the applicable Criminal Procedure Rules, Criminal Practice Directions and disclosure requirements. Conclusions are explained clearly, with any limitations or areas of uncertainty identified.
Expert Witness Services applies a quality-assurance process to completed reports before they are issued.
Frequently Asked Questions
Can John accept instructions from both the prosecution and defence?
Yes. John accepts appropriate instructions from both prosecution and defence teams. His duty is to provide an independent and impartial opinion within his areas of expertise.
What information is needed for an initial enquiry?
Please provide a short case summary, the alleged offences, the court, relevant deadlines, the questions the expert may need to address and how the work will be funded. Case material can be requested after the initial discussion.
Are Legal Aid Agency funded cases accepted?
Yes, Legal Aid Agency funded cases can be considered. A copy of the relevant funding authority will normally be required before work begins.
Can John review another expert’s report?
Yes. John can review existing expert evidence within his specialist fields and identify areas requiring clarification, further analysis or challenge.
How long does an expert report take?
Timescales depend on the volume and complexity of the evidence and any court deadline. With a team of experienced experts, we are used to completing reports at short notice if required. An estimated delivery date will be provided after the initial material has been reviewed.
Discuss an Instruction
To discuss whether Ian’s expertise is suitable for your case, send a brief initial enquiry. Please include the alleged offences, the court, relevant deadlines and whether the matter is privately or publicly funded. Do not send confidential case material until suitable transfer arrangements have been agreed.