fingerprints week 4

Question 1

what are examples of marks evidence?(4)

Answer 1

-finger marks
- bite marks
- tool marks
- ear marks

Question 2

what is mark evidence?

Answer 2

all evidence where an impression of an item is left at the crime scene

Question 3

why was thomas bewick important in the history of fingerprints?

Answer 3

he recognised the individuality of his own fingerprints as a metal engraver

Question 4

why was william herschel important in the history of fingerprints?

Answer 4

he was a brit army officer who identified everyone’s fingerprints were unique, he documented his fingerprints over time to prove provenance. he also used fingerprints on contracts for payments

Question 5

why was henry faulds important in the history of fingerprints?

Answer 5

• involved in archaelogical diggs-noticed fingerprints
• first person to suggest this could identify criminals
  -his idea was declined by scotland yard

Question 6

why was francis galton important in the history of fingerprints?

Answer 6

-split fingerpints down into 8 categories
- estimated probability of 2 persons having the same fingerprint 1 in 64 bil

Question 6

why was edward henry important in the history of fingerprints?

Answer 6

classified fingerprints further
responsible for the first fingerprint classification ‘henry system’

Question 7

what are the 3 layers of human skin?

Answer 7

top layer: epidermis
middle layer: dermis
bottom layer: hypodermia

Question 8

in sweat what are the most important features which help identify a donor of fingerprints?

Answer 8

• amino acids
• fats
  -oils

Question 9

what is the difference between latent and patent fingermarks?

Answer 9

latent-only seen after development
patent- plainly visible with no need for development but may be enhanced with developing agent

Question 10

what are the 3 fingerprint patterns?

Answer 10

• arch
  -loop
  -whorl

Question 11

what is an arch in a fingerprint?

Answer 11

ridges run continuously from one side of the finger to the other with no backwards turn

Question 12

what is a loop in a fingerprint?

Answer 12

prints that recurve back on themselves (180 degrees) and have one delta

Question 13

what is a whorl in fingerprints?

Answer 13

prints that form a circular or spiral pattern with 2 x deltas

Question 14

what are the 4 types of whorl?

Answer 14

• plain (concentric circles)
• central pocketloop w/whorl at the end)
• double loop (s)
• accidental loop(irregular shape)

Question 15

what are the individual characteristics of the Galton details?

Answer 15

ridge ending
bifurcation

Question 16

what is a ridge ending?

Answer 16

where a ridge stops abruptly

Question 17

what is a bifurcation?

Answer 17

where a ridge divides into two ridges

Question 18

during identification of fingerprints what is compared?

Answer 18

pattern type similarity (whorl etc)
characteristic siiliarity (galton details)
poroscopy( study of pores on ridges)

Question 19

what are the 3 parts of the palm print?

Answer 19

-interdigital
- hypothenar
-thenar

Question 20

what powders can you use to recover finger prints on non-porous surfaces? what powder is used is dependent on what?

Answer 20

powders:
-aluminium powder
-black powder
-iron powder
what powder is dependent on the contrast of colours of the powder and surface that you are putting it on