In drug cases, breaking the sample chain or violation of laboratory procedures is one of the strongest points of objection for the defense. In this article, critical control points encountered in practice are discussed.
Sample Chain (Chain of Custody)
- Sample collection (who, when, where, under what conditions).
- Sealing (seal number, seal marks).
- Transport (who, when, with which vehicle, temperature conditions).
- Delivery to laboratory (time stamp, signature of recipient).
- Sample opening/processing minutes during the analysis phase.
Common Procedural Violations
Laboratory Accreditation
The laboratory that will perform forensic analysis must have TÜRKAK accreditation (TS EN ISO/IEC 17025) and forensic medicine standard documents. The result obtained from a non-accredited laboratory is an area of rapid objection for the defense.
Supreme Court 10th CD — Principle
10. CD states that convictions based on evidence that has not been obtained in accordance with the law or whose chain has been broken can be evaluated within the scope of "unlawful evidence" (CMK art. 206/2-a, art. 217/2); It is accepted that the file may need to be corrupted or the evidence may have to be given up, depending on the severity of the procedural violation.
Method of Objection
- Requesting and step-by-step control of minutes.
- Technical evaluation with counter-expert report.
- Quality records of the laboratory, calibration documents.
- Showing contradictions with the timeline submitted to the file.
The sample chain is the backbone of a vigilant defense; It should be examined together with experienced drug crimes lawyer.