Evidence, packaging & storage

Question 1

What is Locard’s Law?

Answer 1

Every contact leaves a trace.

Question 2

What is primary transfer?

Answer 2

Direct contact between 2 items.

Question 3

What is secondary transfer?

Answer 3

Indirect transfer to a 3rd item, e.g. victim > suspect > friend.

Question 4

What does integrity refer to in evidence?

Answer 4

State evidence is in and how well protected from damage, interference, contamination.

Question 5

What is contamination?

Answer 5

Unwanted transfer material from another source to a piece of physical evidence.

Question 6

What is cross contamination?

Answer 6

Unwanted transfer between 2 or more sources of physical evidence.

Question 7

What is the chain of custody?

Answer 7

A continuous, documented log of all evidence transfers and handlers, proving the evidence’s integrity.

Ensures evidence hasn’t been tampered with, altered or contaminated. Critical for evidence to be admissible in court.

Question 8

What are contemporaneous notes?

Answer 8

Detailed, real-time notes of all actions taken with evidence.

Support validity in court, prevent forgetting. Contain date, time, location, description, camera settings and equipment, continuity labels, lighting.

Question 9

What is a continuity label?

Answer 9

A physical label directly attached to evidence, essential info about evidence.

Written as MLP/1 (first initial middle initial last name initial/evidence number) - exhibit reference no. Must be signed.

Question 10

What are the three ‘C’ components?

Answer 10

Help maintain the reliability, security, and clarity of evidence handling.

Question 11

What is physical evidence?

Answer 11

Tangible objects that can be directly handled and examined.

Question 12

What is trace evidence?

Answer 12

Small particles that link suspect or object to crime scene, e.g. hair.

Question 13

What is impression evidence?

Answer 13

Marks left by objects, e.g. footprints.

Question 14

What is photographic evidence?

Answer 14

Images captured to document crime scenes, evidence and suspect injuries.

Question 15

What is digital evidence?

Answer 15

Electronic data retrieved from digital devices, e.g. CCTV, internet history.

Question 16

What is testimonial evidence?

Answer 16

Statements made under oath by witness/experts, provide context or support other evidence.

Question 17

What is resultant (lab) evidence?

Answer 17

Findings from lab test and analysis, e.g. DNA results.

Question 18

What are visible prints?

Answer 18

Clearly seen fingerprints.

Question 19

What are latent prints?

Answer 19

Enhanced with powders/chemical treatments; photo before lifting ensures intact record.

Question 20

What are plastic (impressed) prints?

Answer 20

Oblique lighting to capture 3D aspects of impressed prints on materials like wax/clay.

Question 21

What was significant about the O.J. Simpson Case (1994)?

Answer 21

Footwear evidence included size 12 bloody footprints, traced to a rare shoe type worn by Simpson but he was found not guilty.

Question 22

What are tamper-proof evidence bags used for?

Answer 22

Used for dry items/items needing to be frozen.

Plastic bags labelled and sealed. Permanent markers used to write on label without damaging bag.

Question 23

What are breathable evidence bags used for?

Answer 23

For items that need airflow, e.g. clothing or shoes which may contain biological evidence.

Prevent moisture buildup which could degrade DNA/other biological samples.

Question 24

What are nylon bags designed for?

Answer 24

Specifically for fire debris collection.

Nylon = impermeable to volatile chemicals which helps preserve accelerants or fuel residues.

Question 25

What are polypots and universal containers used for?

Answer 25

For small evidence and prevent damage to fragile evidence, e.g. cigarette ends or glass shards.

Question 26

What are paper bags suitable for?

Answer 26

Items like dry blood-stained clothing/organic materials that require some breathability but shouldn’t be sealed airtight.

Prevent bacterial growth which can occur if item is sealed in plastic.

Question 27

What are weapon tubes used for?

Answer 27

Store sharp objects, ensuring safety during handling and protect unique characteristics of item.

Question 28

What are J-Lar Tape/Gelatine Lifts?

Answer 28

Adhesive materials used to lift trace evidence (e.g. fibres).

Lifts placed on clear backing sheets and labelled to identify the source area.

Question 29

What are swabs used for?

Answer 29

Collecting biological samples (e.g. blood).

Each swab stored in a sterile, sealed package with batch no. and handling details for continuity tracking.

Question 30

What is Beecham’s wrap used for?

Answer 30

Protect delicate/trace evidence, e.g. single fibre.

Question 31

What is the importance of consistency in exhibit labels?

Answer 31

Exhibit labels must be consistent across all items, following SOPs set by agency/lab.

Question 32

What is dry storage used for?

Answer 32

Non-biological items, e.g. dry trace evidence, fibres.

Kept in cool, dry environment to prevent degradation/moisture damage.

Question 33

What is refrigerated storage used for?

Answer 33

Biological samples, e.g. blood collected for toxicology testing.

Stored in fridge at 4 degrees to slow bacterial growth and preserve DNA integrity.

Question 34

What is frozen storage used for?

Answer 34

DNA samples that need long term preservation.

Freezing at -20 degrees to prevent DNA degradation over extended periods.

Question 35

What is ventilated (breathable) storage used for?

Answer 35

Items that need to breathe, e.g. damp clothing with biological evidence.

Stored in breathable paper bags or ventilated areas to prevent mould growth.

Question 36

What is specialized storage for fire debris?

Answer 36

Fire debris containing accelerants or fuel residues.

Stored in airtight, non-reactive containers to prevent volatile compounds from evaporating.

Question 37

What is controlled access in evidence storage?

Answer 37

Evidence storage areas must have restricted access with logs recording every entry and exit.