Packaging and Transportation of Digital Evidence

Why Packaging Matters for Digital Evidence

Digital evidence is fragile in ways that physical evidence is not. A hard drive, smartphone, USB flash drive, or memory card stores data as microscopic magnetic or electronic states. Those states can be destroyed or altered by electrostatic discharge (ESD), electromagnetic interference (EMI), heat, moisture, and physical shock — long before the item ever reaches the laboratory. Proper packaging is the technician's first line of defense against data loss after the item leaves the scene.

Faulty packaging is also a legal problem. If you cannot prove that evidence arrived at the lab in the same condition it left the scene, the chain of custody is broken and the evidence may be ruled inadmissible. Every packaging choice you make must be defensible in court.

The Five Categories of Digital Evidence and Their Packaging Requirements

1. Mobile devices (smartphones, tablets, GPS units). These devices may still be connected to a cellular or Wi-Fi network. A live connection allows remote wipe commands to destroy data in seconds. The correct container is a Faraday bag — a shielded enclosure that blocks all radio-frequency signals. Place the device directly into the Faraday bag without powering it off if it is already on (powering it off may trigger encryption or wipe routines depending on the device). Seal the bag, then place it inside a rigid cardboard box with padding to prevent physical shock. Apply a tamper-evident seal across the box seam and complete the evidence label before transport.

2. Hard drives and solid-state drives (removed from computers). These components are sensitive to ESD. A static discharge of only a few hundred volts — invisible and unfelt by a human — can corrupt data or physically damage circuitry. Use an anti-static bag (typically pink or silver in color) as the primary container. Do not use ordinary plastic bags, which generate static. After sealing the anti-static bag, cushion it inside a rigid cardboard box with bubble wrap or foam. ESD is the primary threat; radio shielding is not required for bare drives that are already powered off.

3. Desktop and laptop computers (intact systems). Keep the system in the state found whenever possible — do not power on or off unless directed by a supervisor or agency protocol. Tape all ports shut with evidence tape to prevent anything from being inserted or removed. Wrap the unit in anti-static bubble wrap, box it, pad all voids, and seal with tamper-evident tape. Label all exterior surfaces and cables that were attached; bag cables separately and label them to match the parent unit.

4. Removable media (USB drives, SD cards, optical discs). These small items are easy to lose and easy to contaminate. Place each item individually in a small anti-static bag, label it, and place all bags together in a single labeled rigid container. Optical discs should be handled by the edges, placed in a jewel case or paper sleeve — never in a sleeve that can scratch the reading surface — then into an anti-static bag.

5. Network equipment (routers, switches, access points). These devices may hold volatile routing tables, logs, and DHCP leases that exist only in RAM. If the device is powered on, consult your supervisor before unplugging it; in some investigations a live acquisition is performed first. Once it is ready to be packaged, use anti-static bags and rigid boxing. Faraday bags are used if wireless transmission is a concern.

Temperature, Humidity, and Electromagnetic Hazards

Heat is a serious threat to all storage media. The interior of a vehicle trunk on a summer day can exceed 140 °F (60 °C). At those temperatures, magnetic domains on hard drives shift, flash memory cells degrade faster, and adhesives inside optical drives soften. Never leave packaged digital evidence in a vehicle trunk, on a dashboard, or in direct sunlight during transport.

High humidity promotes corrosion of circuit board contacts and connector pins. Evidence should not be stored in basements, outdoors in rain, or anywhere condensation can form inside the packaging.

Electromagnetic sources — including large speakers, MRI machines, industrial motors, and radio transmitters — can corrupt magnetic storage media. Keep packaged evidence well away from these sources during transport and storage.

Labels and Chain of Custody

Every package must carry a completed evidence label before it leaves the scene. Required fields typically include: case number, item number, description of item, collection date and time, location collected, collector's name and badge or ID number, and any special handling notes. Use a permanent marker directly on the label — never on the device itself. After labeling, apply a tamper-evident seal across all closures. A broken or missing seal at the receiving end is a discrepancy that must be documented immediately.

The chain-of-custody form travels with the evidence or is logged in a system at each transfer. Every person who takes possession of the item signs, dates, and notes the reason for the transfer. Gaps in this record weaken the legal value of the evidence.

Safety Points

Wear nitrile gloves throughout packaging operations. Gloves protect the evidence from fingerprint contamination and protect you from unknown substances on the device. Do not wear wool or synthetic-fiber clothing near bare circuit boards — these fabrics generate static. If you are working with evidence from a scene involving biological hazards (blood, bodily fluids on a device), treat the item as a biohazard first: bag it in an appropriate biohazard bag before placing it into an anti-static or Faraday bag, and note the hazard on the label.