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Preserving Evidence
From crime scene to forensic laboratory to courtroom, all evidence must be identified, inventoried and secured to preserve its integrity. It is important to demonstrate that the evidence introduced at trial is the same evidence collected at the crime scene and that access was controlled and documented. An understanding of and adherence to the rules governing chain of custody is vital for an investigator to ensure evidence admissibility in court.
Effective evidence preservation includes appropriate packaging with correct and consistent information on labeling and procedural documentation for all items.
Biological evidence should be air-dried before packaging to minimize degradation. Packaging in paper is preferred; however, some laboratories allow packaging in plastic if the sample is thoroughly dried.
Liquid samples, such as water from a toilet bowl or pipes, should be properly documented and packaged in sterile glass or plastic containers and refrigerated as soon as possible.
Additional Online Courses
- What Every First Responding Officer Should Know About DNA Evidence
- Collecting DNA Evidence at Property Crime Scenes
- DNA – A Prosecutor’s Practice Notebook
- Crime Scene and DNA Basics
- Laboratory Safety Programs
- DNA Amplification
- Population Genetics and Statistics
- Non-STR DNA Markers: SNPs, Y-STRs, LCN and mtDNA
- Firearms Examiner Training
- Forensic DNA Education for Law Enforcement Decisionmakers
- What Every Investigator and Evidence Technician Should Know About DNA Evidence
- Principles of Forensic DNA for Officers of the Court
- Law 101: Legal Guide for the Forensic Expert
- Laboratory Orientation and Testing of Body Fluids and Tissues
- DNA Extraction and Quantitation
- STR Data Analysis and Interpretation
- Communication Skills, Report Writing, and Courtroom Testimony
- Español for Law Enforcement
- Amplified DNA Product Separation for Forensic Analysts