Locards principle

What is Locard’s Exchange Principle?

Every contact leaves a trace

What does Locard’s Principle mean in forensics?

Suspect and scene transfer evidence between each other

Why is Locard’s Principle important?

It helps link suspects to crime scenes

What is chain of custody?

Documentation of who handled evidence from collection to court

Why is chain of custody important?

Prevents contamination and ensures evidence is valid in court

What can break chain of custody?

Unrecorded handling or contamination of evidence

What is contamination in forensics?

When evidence is altered or mixed with other material

Why is contamination a problem?

It makes evidence unreliable or unusable

Why must evidence bags be used?

To protect evidence from contamination

Why are gloves used at crime scenes?

To prevent transfer of DNA or fingerprints

Why is labelling evidence important?

To track source, time, and handling of evidence

What should be recorded when collecting evidence?

Time, location, collector, and description

What is proper evidence handling procedure?

Collect, label, store, and document carefully

Why is documentation important in forensics?

It ensures evidence is legally acceptable

What are tool marks?

Impressions or scratches left by a tool on a surface

How are tool marks formed?

By contact between a tool and another material

What can tool marks show?

Type of tool used and possible match to a specific tool

What is wear and tear in tool marks?

Unique changes to a tool over time

Why is wear and tear important?

It makes each tool mark unique

How are tool marks matched?

By comparing marks from crime scene and suspected tool

What is the limitation of tool mark analysis?

Not always 100% certain match

What is forensic odontology?

Use of teeth for identification in forensic science

What can teeth be used to determine?

Identity, age, and sometimes bite mark evidence

Why are teeth useful in forensics?

They are durable and survive decomposition

What is a limitation of using teeth?

Not as accurate as DNA or fingerprints

Why are bite marks unreliable?

They can change and are not always unique

How do teeth help in disasters?

Used to identify bodies when other methods fail

Why is dental evidence considered secondary?

Because DNA is more accurate

What is the main weakness of tool marks?

They may not provide exact identification

Why must tools be examined carefully?

Small differences affect matching accuracy