The chain of custody is managed by an evidence-intake unit within a crime lab. This unit is responsible for receiving evidence and assigning it a unique identifier, often using a bar-code system to track its location within the lab at any time. This system ensures accountability and integrity of the evidence throughout the forensic process.
Who Oversees the Chain of Custody?
The evidence-intake unit oversees the chain of custody in a crime lab. This unit ensures that all evidence is properly documented, securely stored, and tracked from the moment it enters the lab until it is assigned to an examiner.
What Is the Role of the Evidence-Intake Unit?
The evidence-intake unit plays a crucial role in maintaining the integrity of evidence. Its responsibilities include:
- Receiving and logging evidence.
- Assigning unique identifiers (e.g., bar codes).
- Tracking the location of evidence within the lab.
- Ensuring secure storage of evidence.
How Does the Bar-Code System Work?
The bar-code system automates the chain of custody, providing real-time tracking of evidence. Each item is affixed with a bar code that is scanned and tracked by computer, allowing lab personnel to determine its location at any time.
Where Is Evidence Stored?
After logging, evidence is stored in a secure environment, such as a temporary or main storage area. Examiners may also have separate storage areas for evidence assigned to them.
What Happens After Evidence Is Logged?
Once logged, evidence is assigned to one or more examiners for analysis. The type of analysis depends on the nature of the evidence and the specific unit within the crime lab.
What Are the Different Units in a Crime Lab?
Crime labs have various units specializing in different types of evidence:
- Drug Unit: Analyzes illicit drugs and unknown substances.
- Biology Unit: Examines blood, semen, saliva, bones, and other biological materials.
- Trace-Evidence Unit: Analyzes fibers, fire residues, glass, soil, and other trace materials.
- Firearms and Tool-Marks Unit: Compares bullets and cartridges to weapons.
- Fingerprint Unit: Processes latent and patent fingerprints.
- Questioned-Documents Unit: Analyzes handwriting, typewriting, and documents.
- Toxicology Unit: Determines the presence of drugs or poisons in bodily fluids.
- Digital Unit: Handles digital photographs and data from computers and electronics.
Why Is Chain of Custody Important?
Maintaining a proper chain of custody is essential for ensuring the admissibility of evidence in court. It verifies the integrity and authenticity of the evidence, preventing any claims of tampering or contamination.
Want to discover more about the specific processes within each crime lab unit?