Packaging, Sealing, and Labeling Standards

Why Packaging Matters

Evidence packaging is not a clerical task — it is a legal safeguard. A package that is torn, mislabeled, or made of the wrong material can allow a defense attorney to challenge the integrity of every item inside. Courts expect an unbroken chain of custody from the moment an item leaves the scene to the moment it is presented at trial. Proper packaging, sealing, and labeling form the physical backbone of that chain.

Choosing the Right Container

The container must match the physical and chemical nature of the evidence.

Paper bags and envelopes are the default for biological evidence — blood-stained clothing, swabs, hair, and tissue. Biological material needs to breathe. Trapping it in airtight plastic promotes mold and bacterial growth that degrades DNA and can render a sample untestable. Use paper bags sized so the item fits without being crushed, and fold and seal the top before taping.

Plastic bags are appropriate for non-biological items that must be protected from contamination or moisture loss — drug residue, questioned documents, metal fragments, and dry chemical evidence. Never place wet or moist biological material in plastic.

Rigid cardboard evidence boxes protect fragile items: bones, firearms, large electronics, or anything that could be damaged by a bag folding under its own weight. Line the interior with clean paper and secure the item so it cannot shift during transport.

Faraday bags are metallic-lined pouches that block all radio-frequency signals. Use them for powered-on mobile phones, tablets, GPS units, and other wireless devices. If a phone remains connected to a network, remote wipe commands or data sync events can alter or destroy stored evidence. A Faraday bag severs that connection immediately.

Anti-static bags (the silver or pink poly bags you may recognize from computer hardware packaging) protect electronic components — circuit boards, USB drives, and memory cards — from electrostatic discharge that can corrupt stored data. They do not block radio signals, so they are not a substitute for Faraday bags when a device is powered on.

Desiccants (silica gel packets) may be added inside the outer container when packaging biological swabs or items from humid environments to slow moisture-related degradation. Always place the desiccant outside the primary inner packaging so it does not directly contact the evidence.

Impression Evidence and Fragile Items

Cast impressions (plaster or dental stone casts of shoe prints, tire tracks, or tool marks) are rigid and brittle. Wrap them in clean paper first, then place them in a rigid box with padding. Never stack other items on top. Lifting tape with latent prints on it should be placed on a card and stored flat inside a rigid envelope or small box.

Sealing with Evidence Tape

Every opening of a package must be sealed with evidence tape — a paper or plastic tape specifically manufactured to show tampering (it tears visibly if removed and cannot be re-adhered cleanly). General rules:

• Apply tape over every seam and opening, including the fold of a paper bag.
• Initial or sign across the tape-to-package junction so that any tampering breaks your signature.
• A single strip of regular transparent tape is never acceptable as an evidence seal.

If you must reopen a package at the lab, cut the original seal rather than removing it, document the re-opening on the label and in the case notes, re-seal with new tape, and initial again.

Completing the Label — No Blanks Allowed

Every package must carry a label (pre-printed or hand-written in permanent marker) with all of the following fields completed before the item leaves your hands:

1. Case number — assigned by your agency; never leave this blank or write it later.

2. Item number — sequential within the case (Item 1, Item 2, etc.).

3. Brief description — what the item is and its condition at collection (e.g., "Blue denim jacket, bloodstain on left sleeve").

4. Date collected — month/day/year.

5. Time collected — use 24-hour (military) time to avoid AM/PM ambiguity.

6. Collector's name and signature — the person who physically packaged the item.

7. Location collected — specific enough to relocate the exact spot (e.g., "Living room floor, 3 ft east of front door").

Leaving any field blank creates a gap in the chain of custody. If you genuinely do not yet know a value, consult your supervisor before sealing.

Safety Considerations

Packaging biological evidence carries exposure risk. Always wear nitrile or latex gloves when handling blood-stained items, swabs, or tissue. If a sharp object (broken glass, a knife) must be packaged, place it in a rigid container first or use puncture-resistant packaging; never reach into a bag that might contain sharps. For chemical evidence with unknown properties, consult the hazardous materials officer and use appropriate PPE (face shield, chemical-resistant gloves, fume controls) before packaging. Change gloves between evidence items to prevent cross-contamination.

Quick Reference — Container Decision Logic

| Evidence Category | Primary Container | Reason |

|---|---|---|

| Biological (wet or dry) | Paper bag/envelope | Allows moisture vapor to escape; prevents mold |

| Non-biological solids/dry chemicals | Plastic bag | Seals against outside contamination |

| Fragile or oversized items | Rigid cardboard box | Physical protection |

| Powered-on digital device | Faraday bag | Blocks RF signals; prevents remote wipe |

| Electronic components (unpowered) | Anti-static bag | Prevents electrostatic discharge |

| Impression casts | Paper wrap + rigid box | Protects brittle surface |

When in doubt, choose the container type that protects evidence integrity while preventing contamination of either the evidence or the examiner.