The Daubert-Kumho Test

The DAUBERT-KUMHO Test happens to be the new test of expert testimony. The trial Judge is to determine whether or not the Expert Witness has expounded upon the stature of scientific knowledge. It consists of four factors

1. Testing of the theory

2. Review of peers of the technique

3. Potential rate of error

4. The theory of technique generally accepted

References:

Garland Norman (2006) Mc Graw Hill, Criminal Evidence Fifth Edition 

The Precipitin Test

The precipitin test identifies whether or not blood found on a crime scene is human or another species. Knowing the origin of the blood helps the forensic lab determine whose blood it is. The precipitin test can be preformed directly at the crime scene, this way you do not have to send false samples to the laboratory.

The precipitin test measures the response from the immune system of another animal by making anti-human antibodies to protect from human blood proteins.  Anti bodies located in the other animal’s blood identify specific foreign pathogens that come from human blood molecules. The animal’s antibodies detection of these foreign human molecules forces the animal to create anti-human antibodies that attack antigens (foreign blood molecules).

When human blood is introduced to the animal’s anti- human antibodies it produces a clot called a precipitate clot. This precipitate clot can be formed in a test valve identifying whether or not a blood sample is human or not. This test is called the Precipitin Test. 

1. 1.      Animal is injected with human blood
2. 2.      Animal makes anti-human antibodies
3. 3.      Animal blood is extracted
4. 4.      The extracted animal blood is used to test other blood to identify whether the blood is of human origin

References:

http://www.bukisa.com/articles/103653_the-physical-and-biological-aspects-of-forensic-science

http://www.slideshare.net/smullen57/1-chapter12-blood

http://www.clt.uwa.edu.au/__data/page/112508/fsb04.pdf