Module 2: Chain of Custody and Evidence Packaging - Part 2

Evidence Packaging

Introduction to Evidence Packaging

• Importance of proper evidence packaging to maintain integrity and avoid contamination or damage.

• Example of improper packaging: Gas can improperly packed.

Packaging Materials

• General Guidelines

  • Avoid plastic for biological evidence or items that need to breathe.

  • Plastic Usage: Appropriate for non-biological items, e.g., tools, and specific drug evidence.

Specific Evidence Types

Drugs

• Use of plastic packaging:

  • Suitable for drugs such as LSD on blotter paper, tablets (temporary storage).

  • K Pak packaging recommended:

  • Heat sealed and airtight designed specifically for drugs.

  • Helps protect against exposure to hazardous chemicals.

• Limitations of plastic:

  • Not suitable for fresh plant material due to degradation risks.

• K Pak packaging should accommodate:

  • Different forms of drugs (liquids, syringes, powders, sticky tars).

  • Health hazards and potent drugs in small amounts.

• Packaging Procedures:

  • Liquid evidence: pour into a vial, retain original container in a paper sack.

  • Powders/tablets: collect with scoop into vials, package in paper envelopes.

  • Package syringes in specially designed tubes to avoid punctures.

Trace Evidence

• Collection and packaging:

  • Requires meticulous methods; documentation of evidence location is crucial.

  • Removal techniques:

  • Use tweezers or tape lifts for evidence collection (i.e., hairs, fibers).

  • Sticky tape can be used on furniture to collect evidence, mark location clearly.

  • Package sticky tape or paper in appropriately sized envelopes or bindles.

Firearms

• Important considerations:

  • Record condition (e.g., hammer position, safety, controls).

  • Document fired/unfired cartridges, visible trace evidence, and do not package loaded firearms.

• Firearm handling:

  • Ensure firearms are unloaded and handled by non-fingerprint prone surfaces.

  • Do not insert objects into the barrel (can damage lands and grooves).

• Proper storage:

  • Use specialized boxes with plastic ties to immobilize weapons and label correctly.

  • If biological evidence is present, mark with a biohazard label.

Projectiles & Cartridges

• Care during handling:

  • Protect crucial markings (striations) on bullets, do not mark bullets or use metal forceps to pick them up.

  • Recommended handling: gloved fingers, plastic forceps if necessary.

• Packaging recommendations:

  • Wrap projectiles in paper bindles or soft tissue paper.

  • Use appropriately sized containers to avoid movement and damage.

Knives

• Recommended handling:

  • Do not package directly in paper envelopes.

  • Use tubes or boxes to secure knives and prevent damage.

Debris Evidence

• Submission method:

  • Use clean metal cans to hold debris evidence containing ignitable liquid residues.

  • Optional charcoal strips can be placed in the can for vapor collection in lab analysis.

• Analyzing ignitable residues:

  • Solvent extraction from the charcoal strip to analyze using gas chromatography mass spectrometry (GC-MS).

  • Distinct chromatographic profiles help identify specific ignitable liquids.

Evidence Processing Labs

• Importance of selecting proper forensic labs:

  • Labs must be designed specifically for forensic testing and familiar with proper techniques.

  • Proper chain of custody protocols and handling methods are critical.

• Limitations in access:

  • Some regions may have few or no reliable labs. International transport may be necessary.

  • In the US, noted lab for wildlife crimes: US Fish and Wildlife Forensics Lab, Ashland, Oregon.

• Specific considerations for wildlife cases:

  • Diverse types and sources of evidence (e.g., caviar, fur, meat).

  • Labs may need to assess origin of items and compliance with environmental laws.

Conclusion

• Careful packaging and labeling are essential to integrity and quality of evidence.

• The importance of choosing the right lab and understanding their capabilities is paramount for effective forensic analysis.