w5 forensic strategy & interpretation Flashcards
based on the case scenario, what samples/clothing would you analyse first?
the intimate samples (both vaginal swabs , anal swabs and mouth swabs). if info is found, send it for dna analysis and once the dna profile has been produced, check against the national dna database
if there is no semen found on the intimate swabs, what information can we gather?
- no condom
- no ejaculation
- didnt happen
key information to draw from the case
found unconscious by dog walker
no obvious injuries
cause of death = blunt trauma
unknown female
no suspect or information about what has happened
dont know if she has been assaulted
other matters
is the deceased in a sexually active relationship
in the absence of suspect, might need to use the NDNAD
reuest diagaram or notes on deceased injuries
issues to address
who is the female
any evidence to support an assault, that would result in head injuries
any evidence to support recent sexual ectivirty
could she have been assaulted where she was found?
punching and kicking - what clothing sample is the top priority to analyse
trainers for blood
either on front of shoe or on sole
pauls account
doesn’t know how john is
saw a fight was going on and got involved
what should be addressed
did paul punch and kick john , as alleged
examine the footwear
propositions
hp paul punched and kicked john as alleged
hd = paul did not punch and kick john as alleged
likelihood ratio
Lr = Pr (E/Hp) / Pr (E/Hd)
need to calculate E
potential outcomes on footwear
no blood hp is true = 0.5 0.95 0.52 0.4 0.0049 10 0.1 0.001 100
potential outcomes on jumper
sexual assault scenario - what should be addressed?
did suspect have vaginal intercourse with the complainant that night or was it 4 days earlier
potential outcomes on high vaginal swab
no semen = 0.1 0.95 0.1
some semen = 0.2 0.049 4
lots of semen = 0.7 0.001 700
