FORENSIC EXPERT WITNESS STATEMENT
(Criminal Justice Act 1967,s.9; M.C.Act 1980, ss. 5A(3A) and 5B; M.C. Rules 1981. R.70)
STATEMENT OF: Isabella Severino
DATE OF BIRTH OF WITNESS: 19/07/2006
OCCUPATION OF WITNESS: Forensic Scientist
Thames Valley Police, Wendover Rd, Aylesbury HP21 7LA
This statement (consisting of 9 page(s) each signed by me) is true to the best of my knowledge
and belief and I make it knowing that, if it is tendered in evidence, I shall be liable to prosecution if
I have wilfully stated in it anything which I know to be false or do not believe to be true.
DATED: 10/03/2023 - 24/03/2023
SIGNATURE: Isabella Severino
QUALIFICATIONS AND EXPERIENCE OF WITNESS
I have a BSC in forensic science of biological, chemical and physical evidence and i have worked
in the field for 2 ½ years.
RECEIPT OF ITEMS
From records available to me, I understand that the exhibits listed below were received at
Thames Valley Laboratory. In relation to the case 52.
EXHIBITS
● 01 - fingerprints - There were many fingerprints left at the crime scene from the criminal. It
can help narrow down the link of a suspect to a crime scene.
● 02 - hair - Strands of black hair were found at the crime scene, especially on the victim's
body.
● 03 - note from the crime scene - The note left at the crime scene threatens the victim and
was left on their body.
● 04 - footprints - across the entire crime scene fingerprint impressions were left.
● 05 - blood samples - The quantity of blood at the crime scene such as pools and spatters.
This was all the evidence submitted to me and the results of the examination are detailed below.
FORENSIC EXPERT WITNESS STATEMENT
(Criminal Justice Act 1967,s.9; M.C.Act 1980, ss. 5A(3A) and 5B; M.C. Rules 1981. R.70)
01 - fingerprints:
PURPOSE OF THE EXAMINATION
The analysis of the fingerprints found at the crime scene was to determine which suspect can be
linked to the crime. By comparing the fingerprints of the ones collected at the scene, to the
, suspects fingerprint samples, meant that the individual characteristics of the fingerprints can be
compared and possibly linked.
RESULTS OF THE EXAMINATION
The results I gathered from examining the fingerprints from the crime scene, and comparing this
to samples given by our three suspects. We examined all of these samples, identifying the
characteristics of each of the fingerprints. I believe that suspect B’s fingerprints, match the
fingerprints discovered at the crime scene. I believe this, as suspect B’s fingerprint characteristics
match that of the crime scene fingerprints such as the crossover, shortridge and bunification of
suspect B’s left thumb. I identified the same characteristics, in the crime scene fingerprints.
INTERPRETATION OF THE RESULTS
From examining the fingerprints, my findings are as follows:
Without a definite match to one of the Suspects, there is a possibility the fingerprints from the
crime scene are from another individual, who was not compared to. This test has decreased in
reliability. As it was only examined once, and the characteristics found in the fingerprints may
have been missed or identified, as different by other examiners. The test was fairly conducted so
it is mostly accurate and I limited contamination by using new equipment for each piece of
evidence. The results would have been more valid, if the test was conducted by other examiners
to double check my findings, were correct and the most accurate.
CONCLUSIONS
(In assessing the significance of the evidence, I have used the following scale: possible, probable
and likely)
In my opinion, the findings present in this report are probable in significance. Exhibit 01 provides
moderate evidence that Suspect B is most probably the person who left their fingerprints at the
crime scene. However further analysis is required to determine this. I would suggest that another
analyst compares my findings to theirs. In doing so, the characteristics discovered by myself and
another analyst can be cross referenced and a final conclusion can be made. The evidence to
support this is the presence of a crossover, shortridge and bunification present on the left thumb
of Suspect B and the original samples from the crime scene. However, similar characteristics of
other fingers were found which matched other suspects' fingerprints to the original ones.
Every individual has unique fingerprints, none are identical to one another, as a result, an exact
match can be found. After examining the personalised characteristics, the exact match can be
found as to who the prints are. The probability of 2 fingerprints matching from 2 separate
individuals is 1 in 64 billion, so if proven, holds great significance. Therefore, I conclude this piece
of evidence is of probable significance.
SCIENTIFIC REASONING
After the SOCO’s enhanced fingerprints were found at the crime scene, I took samples of
fingerprints from all the Suspects. Using a charcoal fingerprint pad, I sampled each suspect's
finger, leaving an impression of their fingerprint to be transferred to white paper, identifying which
finger has been imprinted, for example the left thumb. The fingerprints of all the suspects were
then analysed to identify unique characteristics using a magnifying glass, these would then be
compared to the fingerprints found at the crime scene.
FORENSIC EXPERT WITNESS STATEMENT
