More Trace Evidence

Question 1

What mark and impressions can be left at a crime scene?

Answer 1

Fingerprints
Footprints
Bite marks
Tool marks
Tyre marks

Question 2

What is dactyloscopy

Answer 2

The study of fingerprint identification

Question 3

How are finger prints formed?

Answer 3

They are formed in foetal life, influenced on how baby moves in womb and the speed of growth
They are formed on finger pads

Question 4

What is special about fingerprints?

Answer 4

Unique
Even identical twins differ

Persistence- even if you have superficial damage, your fingerprints stay the same throughout your life (unless deep tissue damage or scarring)

Question 5

Why do we have fingerprints?

Answer 5

Ridges- for grip

Lots of nerve endings in fingertips to help keep you cool

Question 6

What are the classifications of fingerprints?

Answer 6

Loops
Arches
Whorls

Question 7

How many people approximately have loops?

Answer 7

60%

Most common

Question 8

How can you divide ‘loop’ fingerprints?

Answer 8

Radial loops

Ulnar loops

Question 9

What are radial loops?

Answer 9

The loops slant towards the radius bone (thumb side)

Question 10

What is an ulnar loop?

Answer 10

The most common

They slant the other way? Away from radius?

Question 11

What is important to remember about direction of loops?

Answer 11

They go in opposite directions depending on which hand

Question 12

What percentage of the population have arches?

Answer 12

5%

Question 13

What groups can arches be divided into?

Answer 13

Plain arch

Tented arch

Question 14

What is a plain arch?

Answer 14

A mound LIKE pattern

Question 15

What is a tented arch?

Answer 15

Looks like a church steeple

Question 16

How many groups can whorls be divided into?

Answer 16

4

Question 17

What whorl groups are there?

Answer 17

Plain
Central pocket
Double loop
Accidental

Question 18

What is a plain whorl?

Answer 18

A circular spiral pattern

Question 19

What is a central pocket whorl?

Answer 19

A tight circular pattern in the centre of a fingerprint

Question 20

What is a double loop whorl?

Answer 20

Where there are two looped patterns

Question 21

What is an accidental whorl?

Answer 21

An irregular circular pattern

Question 22

How can you identify a print?

Answer 22

At crime scenes

Sweat on fingers or blood can leave impressions on substrate

Question 23

What is a substrate

Answer 23

The surface you leave a print on

Question 24

What is a matrix?

Answer 24

The thing leaving a print on a substrate

Question 25

What are the types of fingerprint impressions?

Answer 25

Latent Visible Plastic

Question 26

What is a latent fingerprint

Answer 26

It is invisible to the naked eye, techniques needed to identify it

Question 27

What is a visible fingerprint?

Answer 27

Clearly seen Can be positive- leaving a mark on a surface e.g. sweat? Or negative- an impression on a surface, like snow?

Question 28

What is a plastic fingerprint?

Answer 28

3D prints on soft surfaces such as clay, soap bar

Question 29

What is ACE-V?

Answer 29

Analysis Compare finger prints Evaluate (weigh up evidence) Verification (independent analysis by 2 fingerprint experts)

Question 30

Footwear

Answer 30

.

Question 31

Bite marks

Answer 31

.

Question 32

What types of footprints can you get?

Answer 32

2d- blood 3D- on mud, soft substrate Negative- take surface cover off something

Question 33

How can you recover footprints?

Answer 33

Photograph Chemical Powders to highlight print Produce a cast if 3D print

Question 34

What can footprints tell us?

Answer 34

General size How a person walks Can compare to a suspect?

Question 35

What sources can you get bite marks from?

Answer 35

Food Skin (subject/victim) Objects

Question 36

What characteristics can you see from bite marks?

Answer 36

Gaps, ridges (top of teeth), position of teeth in mouth, patterns

Question 37

Who examines bite marks?

Answer 37

Forensic odontological

Question 38

How can you preserve bite marks?

Answer 38

Make a cast | Photographs

Question 39

Who was ted bundy?

Answer 39

Raped many women, bite marks convicted him as one of his victims had been bitten

Question 40

What sort of tool marks can be made?

Answer 40

Saw | Screwdriver

Question 41

How can tool marks be analysed?

Answer 41

Comparison of marks | Microscopy

Question 42

What are tyre marks?

Answer 42

Marks formed by tread on tyres

Question 43

What types of tyre marks can you get?

Answer 43

Latent- invisible to naked eye Visible Plastic- 3d

Question 44

What can tyre marks lead to?

Answer 44

Information about make and specification of tyre