Different types of evidence are packaged based on their nature to preserve their integrity and prevent contamination. The general rule of thumb is: wet evidence goes in breathable containers like paper bags or boxes, while dry evidence goes in plastic containers.
Here's a more detailed breakdown:
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Wet or Biological Evidence (e.g., blood, semen, saliva, plant matter): This type of evidence must be packaged in breathable containers such as paper bags, boxes, or envelopes. This allows the moisture to escape, preventing the growth of mold and bacteria, which can degrade the DNA and other biological materials. Never package wet evidence in plastic containers because this traps moisture and encourages degradation. The evidence should also be air-dried as soon as possible before packaging.
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Dry Evidence (e.g., fibers, hairs, paint chips, drugs, documents): Dry evidence can generally be packaged in plastic bags, envelopes, or containers. Plastic provides a secure barrier against outside contaminants.
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Sharp Objects (e.g., knives, needles, broken glass): Sharp objects need to be packaged in rigid, puncture-proof containers to prevent injury to handlers and maintain the integrity of the evidence. These containers should be clearly labeled as containing sharp objects.
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Firearms: Firearms should be rendered safe (unloaded) before being packaged. Each firearm should be individually packaged in a sturdy cardboard box or a specially designed gun box. The serial number should be recorded.
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Trace Evidence: Trace evidence (e.g., small amounts of hair, fibers) should be collected carefully and packaged in a "druggist fold" or placed in a small, clean container like a glass vial or a paper envelope.
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Clothing: Clothing can be packaged in paper bags or boxes. If the clothing is wet with biological fluids, it needs to be air-dried before packaging to prevent degradation.
Key Considerations for All Evidence Packaging:
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Separate Packaging: Items that could cross-contaminate each other must be packaged separately. This prevents mixing of evidence and ensures accurate analysis. For example, different items of clothing from the same crime scene should be packaged individually.
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Sealing and Labeling: All evidence containers must be properly sealed with evidence tape to prevent tampering. The tape should be initialed and dated by the person packaging the evidence. The container should also be clearly labeled with details such as the case number, item description, location collected, date collected, and collector's name.
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Chain of Custody: A detailed chain of custody record must be maintained to track the handling of the evidence from collection to analysis. This record documents who had possession of the evidence, when, and for what purpose. Maintaining a proper chain of custody is crucial for the admissibility of evidence in court.
Proper packaging is vital for maintaining the integrity of evidence, ensuring accurate analysis, and supporting legal proceedings. Following these guidelines helps prevent contamination, degradation, and loss of crucial information.
