Evidence Integrity

• newEditor
• Forensic science
• Higher Education (non-degree)

Evidence Integrity

Learning Outcome 1 Recap

Which of the following best defines evidence integrity?

A

Ensuring the evidence remains in police custody

B

Maintaining the original condition and authenticity of evidence from recovery to court

C

Keeping evidence sealed in plastic bags

D

Recording all evidence in a single notebook

The purpose of the crime scene cordon is to:

A

Prevent public access, evidence loss and contamination

B

Allow media to film the scene safely

C

Mark where the crime occurred for photographs

D

Store recovered evidence

What is the correct sequential order of scene management?

1

Conduct preliminary walkthrough

2

Collect evidence

3

Establish cordon

4

Submit to laboratory

5

Photograph and record scene

Which principle underpins all crime scene work?

A

Speed of collection

B

Integrity of evidence

C

Quantity of items recovered

D

Use of the latest technology

The preliminary walkthrough is conducted to:

A

Immediately collect fragile evidence

B

Identify potential hazards and plan evidence recovery

C

Take witness statements

D

Start forensic testing at the scene

Contamination control is only important for biological evidence.

A

True

B

False

The chain of custody log must only be updated once per shift.

A

True

B

False

Photographs should always be taken before any evidence is moved.

A

True

B

False

Disposable gloves should be changed between handling each item of evidence.

A

True

B

False

Scene sketches must include measurements, direction, and scale.

A

True

B

False

Every person entering the scene must sign the cordon log.

A

True

B

False

Scene notes should be written up after evidence is processed.

A

True

B

False

Which of the following actions would break the chain of custody?

A

Failing to sign an evidence transfer form

B

Using tamper-evident seals

C

Photographing the scene

D

Labelling evidence with unique identifiers

Why is detailed documentation vital for integrity?

A

It protects investigators from prosecution

B

It provides a verifiable record that evidence has not been tampered with

C

It allows police to skip digital logging

D

It replaces the need for photography

The “chain of custody” ensures:

A

Every item’s handling is traceable and accountable

B

The police own the evidence

C

Only one person can handle the evidence

D

Evidence remains in a sealed box until court

What should appear on every evidence label?

A

Collector’s name, date/time, case number, and description

B

Suspect’s name and confession details

C

Evidence weight and colour

D

Officer’s opinion of relevance

What happens if an evidence label falls off?

A

It can be guessed from context

B

The evidence may be inadmissible in court

C

It is still valid if the officer remembers it

D

It is simply reattached later

Why must chain of custody records be tamper-proof?

A

They form part of the legal record

B

They reduce paperwork

C

They show how fast evidence moved

D

They allow edits if mistakes occur

Digital records automatically maintain continuity and do not require manual signing.

A

True

B

False

Each item of evidence should have a unique identification number.

A

True

B

False

A digital photograph must include metadata for time and date verification.

A

True

B

False

Notes written after the scene visit can still be considered official documentation.

A

True

B

False

The continuity log is an optional administrative step.

A

True

B

False

Correct order for documenting a new evidence item:

1

Describe in scene notes →

2

Log into continuity record

3

Seal and sign →

4

Photograph in situ →

5

Collect and label →

Why is contamination control critical for evidence integrity?

A

To make evidence easier to handle

B

To prevent introduction of foreign material that compromises analysis

C

To reduce paperwork

D

To maintain scene aesthetics

Which packaging method best preserves biological evidence like blood-soaked clothing?

A

Airtight plastic bag

B

Paper bag with ventilation

C

Aluminium foil

D

Glass jar

Chemical evidence such as drugs should be stored in:

A

Breathable paper bags

B

Plastic tamper-evident bags or sealed vials

C

Cardboard boxes

D

Cloth bags

Physical evidence such as glass fragments is best contained in:

A

Cotton-lined paper bags

B

Metal tins

C

Hard plastic or cardboard boxes with cushioning

D

Plastic cling film

What is the main reason for avoiding plastic packaging for damp evidence?

A

It causes static electricity

B

It is too expensive

C

It’s not transparent

D

It can promote bacterial growth and degradation

Correct procedure for preserving a wet biological sample:

1

Package in paper bag

2

Log into evidence system

3

Air dry evidence

4

Label and seal

What is the best environment for storing biological samples?

A

Warm and dark

B

Cold, dry, and ventilated

C

Airtight

D

Direct sunlight

Why is aluminium foil sometimes used in forensic packaging?

A

To protect volatile chemical residues from light exposure

B

To reduce cost

C

To make evidence heavier

D

To prevent odours

What technological advancement most directly helped reopen cold cases?

A

Laser scanning

B

Genetic genealogy and database matching

C

Digital photography

D

Voice recognition

Data protection laws do not apply to forensic samples.

A

True

B

False

Correct order for solving a cold case using preserved DNA:

1

Re-test using new DNA methods

2

Identify and confirm suspect

3

Locate preserved evidence

4

Match profile in genealogy or criminal database

The Protection of Freedoms Act 2012 regulates:

A

Police use of firearms

B

Retention and destruction of DNA and fingerprints

C

Jury confidentiality

D

Scene photography rules

Under current UK law, biological samples from unconvicted individuals must:

A

Be destroyed after a defined retention period

B

Be retained indefinitely for research

C

Be archived anonymously

D

Be returned to the suspect

Cold cases rely heavily on well-preserved physical and biological evidence.

A

True

B

False

Correct order for legally compliant evidence management:

1

Secure storage under appropriate conditions

2

Return or destruction as required by law

3

Collect and label

4

Retention review after legal process