Class notes

BPA and its functions in Forensics

0 purchase

Course
Forensics Science (CHEM1025)

Institution
University Of Greenwich

Blood pattern analysis is a helpful tool in forensic science that can aid in crime scene reconstruction. When combined with DNA analysis and other investigation findings, blood evidence can provide more conclusive and detailed details of the sequence of events.

[Show more]

Preview 2 out of 11 pages

View example

Uploaded on July 17, 2023
Number of pages 11
Written in 2022/2023
Type Class notes
Professor(s) Dave dibbs
Contains All classes

bpa
blood

Institution
University of Greenwich
Education Unknown
Course
Forensics Science (CHEM1025)

$7.91

Add to cart

Add to wishlist

100% satisfaction guarantee
Immediately available after payment
Both online and in PDF
No strings attached

Bloodstain Pattern Analysis

▪ A tool used to understand what may have taken place during blood shedding activities:

▪ What, how, when, how many, where

▪ Possible injuries sustained

▪ Possible weapon used

▪ Minimum number of blows, shots or actions

▪ Sequence of events

▪ An understanding of how blood behaves is essential.

▪ Average person contains 4½ to 5 litres of blood

▪ Blood accounts for ≈ 8% of body weight

▪ Blood is made up of cells and plasma or serum

▪ Plasma or serum is ≈ 55% of blood volume

▪ Cells ≈ 45% of blood volume – comprising red blood

cells (99% of cell volume), white blood cells and platelets

▪ Can loose 10% (≈ ½ litre) with no effect

▪ The loss of 35 – 40% (1¾ – 2 litres) typically fatal

▪ Veins ‘leak’ or ‘ooze’

▪ Arteries carry blood with pressure from the heart and are usually deep within the body to prevent
damage.

Phase 1: Searching and documenting

▪ Searching using white light primarily

▪ Level of search will depend on case circumstances, what is found, and what scenarios need to be
considered.

▪ Will always include looking up and under

▪ Finding blood may direct search in different ways:

▪ Follow trails

▪ Direct attention to bloodstain surfaces, e.g. cupboard doors indicates places searched

▪ Suggest activities to investigate further, e.g. bloodstained towels, sink taps indicates clean up

, Phase 2: Once blood is found and documented the analyst will begin to describe the patterns in terms of
possible mechanisms that may have created them. Opinions always documented separately from the
blood to allow for an independent second check.

▪ BPA is a scientific method where the observations are evaluated against specific questions or
hypothesis

▪ What are the questions you have that you would like to try and answer with BPA?

▪ For example: Witness says it was self defence – does BPA support this?

▪ Witness says there was no weapon used – do the bloodstain patterns support this?

Clasifications:

BPA starts from the shape, size, and distribution of the stains From this the analyst will eliminate certain
mechanisms.

All other possible mechanisms will be included until further information rules them out If there is doubt
about an answer more mechanisms will be included. Analysts MUST NOT over state the evidence.

BPA Categories

Different fields of thought on categories of bloodstain patterns.

Passive stains are sometimes known as non-spatter.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller rudhainafirdous. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $7.91. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

69252 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 15 years now

Start selling