Chain of custody documentation is often required for evidence intake in crime laboratories. This documentation tracks evidence from the moment it’s collected until it’s presented in court, ensuring its integrity and admissibility. A bar-code system can generate an automatic chain of custody, making it possible to determine its location in the lab at any time.
Why is Chain of Custody Documentation Important?
Chain of custody is crucial in maintaining the integrity of evidence. It creates a detailed record of every person who handled the evidence, the dates and times it was handled, and what changes, if any, were made to it. Without proper chain of custody, the evidence may be deemed inadmissible in court, potentially jeopardizing a case.
What Items Require Chain of Custody Documentation?
Several types of evidence typically require chain of custody documentation to ensure their integrity and admissibility in court. These include:
- Biological Samples: Blood, semen, saliva, and other bodily fluids used in DNA fingerprinting to identify victims and perpetrators
- Trace Evidence: Fibers, hair, paint chips, and glass fragments that can link a suspect to a crime scene
- Digital Evidence: Data retrieved from computers, personal electronics, and digital photographs, which may contain crucial information related to the case
- Firearms and Tool Marks: Spent bullets and cartridges, as well as tools used in a crime, which can be matched to specific weapons or instruments
- Illicit Drugs: Unknown pills, powders, or liquids that may be illicit, which are analyzed to determine their chemical composition
How Does Chain of Custody Work?
The process begins when evidence is collected at a crime scene or from a person. The evidence is then labeled with a unique identifier, and a chain of custody form is initiated. This form includes:
- Date and Time: When the evidence was collected.
- Location: Where the evidence was found.
- Name of Collector: The person who collected the evidence.
- Description of Evidence: A detailed account of what the evidence is.
- Signatures: Every person who handles the evidence must sign the form, acknowledging their responsibility for it.
What are the consequences of breaking chain of custody?
Failure to maintain a proper chain of custody can have severe consequences in legal proceedings. If the chain of custody is broken, the integrity and authenticity of the evidence come into question, potentially leading to the following outcomes:
- Inadmissibility of Evidence: The court may rule the evidence inadmissible, meaning it cannot be used during the trial.
- Weakened Case: The prosecution’s case may be significantly weakened, making it difficult to secure a conviction.
- Acquittal: The defendant may be acquitted due to lack of reliable evidence.
- Re-trials: If a conviction was based on compromised evidence, the defendant may be granted a re-trial.
How do crime labs maintain chain of custody?
Crime labs use several methods to maintain chain of custody, including:
- Unique Identifiers: Assigning a unique laboratory and case identifier to each item of evidence
- Bar-Code Systems: Using bar codes to track the location of evidence within the lab
- Secure Storage: Storing evidence in a secure environment with limited access
- Documentation: Maintaining detailed records of who handled the evidence and when
Would you like to explore the specific procedures forensic scientists use to collect and preserve different types of evidence at a crime scene?