Ensuring and maintaining the highest standards of integrity, accuracy and reliability throughout the forensic chain is imperative for forensic findings to withstand court scrutiny. For any quality system to be effective, it must be assured at every level, understood and implemented in every task by every lab employee involved in the forensic process from beginning to end. An individual can wreak havoc in the chain. Top management’s commitment to the highest level of service provision and testing quality cannot be overstated. A lack of commitment or lip service to quality by top management can result in laboratory-wide flaws and systemic failures, resulting in far-reaching consequences and serious repercussions for the justice system.
A quality management system in a forensic laboratory ensures the consistency and conformity of forensic science services to a pre-defined set of standards, customer expectations, and the local law. It ensures that laboratory analyses are accurate and repeatable, and customer requirements are met or better still – exceeded. Commitment to quality must also be enforced through continual process improvement, and problem prevention and correction.
The internationally accepted quality standard for testing and calibration laboratories is the ISO/IEC 17025 standard “General Requirements for the Competence of Testing and Calibration Laboratories”. The general requirements within this standard are customised to forensic analysis by the ILAC-G19:2002 guidance document “Guidelines for Forensic Science Laboratories”, and additional forensic criteria such as the ASCLD/LAB Supplemental Requirements. Quality management in most forensic laboratories is based on this standard, as well as forensic-specific supplemental standards, Scientific Work Group guidelines, published best practices and standard test methods. All these are used in conjunction with the laboratory’s policies and procedures, and local laws and regulations.
The quality system in a forensic laboratory comprises four broad categories:
The Forensic Chain: A contractual agreement between a customer and the laboratory marks the start of a case. It is of paramount importance that the integrity of evidence is preserved. Written procedures for scene processing, transport, receipt, handling, protection, storage, retention and disposal of samples must be implemented and adhered to. Evidentiary items are properly identified and packed, and a Chain of Custody Log records and tracks the receipt and internal transfers of these items during the course of analyses and examinations. The primary work product of the analyses and examinations of physical evidence is the forensic report, which serves to communicate the analytical results, interpretations and conclusion in a clear and objective manner. Forensic reports can influence court decisions and are often subject to intense scrutiny in court. The final quality control check comes in the form of a report review where any non-conformity discovered is discussed with the reporting forensic scientist and resolved by corrective action.
Competency of Personnel: Personnel is the most important factor that affects the quality of forensic results. Personnel must possess the knowledge, skills, abilities, training and experience to perform assigned duties to the required standards. They obtain competency in an area of work through training as well as competency testing. Proficiency testing helps to ensure the quality of results, and evaluate the performance and capability of laboratory personnel on a regular and ongoing basis.
Laboratory Facilities, Equipment and Supplies: The security of evidentiary items and prevention from loss, contamination and deterioration are vital in a forensic laboratory. Critical environmental conditions are monitored, controlled and recorded to ensure reliability of test results. Equipment used for sample preparation, measurement and analysis are subjected to quality checks such as maintenance procedures, calibrations and performance checks to ensure that they are performing correctly.
Managing Non-Conforming Work: Having a well-designed and implemented quality system does not mean that a laboratory is immune to errors or lapses in quality. Prompt actions must be taken upon discovery of errors or lapses to rectify the situation. Non-conformity is managed by means of preventive actions, corrective actions, quality audits and reviews, and a continuous improvement culture.
Quality in a forensic laboratory is an ongoing process that requires the commitment of the whole laboratory to continuously improve its quality management system.