DNA testing in forensic investigations is mandatory to solving the criminal cases in ways that are reliable and sound. DNA samples can easily be used to create a DNA profile which can then be compared to the alleged perpetrator. The chances of two people having the exact same DNA are negligible. DNA forensic testing has also found use outside the sphere of criminal forensic investigations too and is used by DNA testing companies as one of their many services in for example, paternity DNA testing.
The Triple Murder
In January, 2007, Wisconsin, Danyetta Lentz and her two children; Nicole Lentz aged 14 and Scott Lentz aged 17. The three were found murdered in their mobile home. The family was found strangled and forensic investigations led to the conviction of James Koepp. It took the criminal court in which Koepp was being tried just 90 minutes to reach their final verdict- guilty. The sentence will not be heard until April but sound speculations and legal professionals state that it is likely to be a life sentence. Koepp already was a convicted sex offender in 1983 when he assaulted two women.
Solving the murder case relied on the use of a number of DNA samples. Advances in DNA testing means that DNA samples can be found in the most difficult places and even tiny traces for DNA can be enough to provide conclusive results.
Amongst the forensic DNA samples gathered by police were:
A neck tie used in the strangling of the victims
DNA found under the nails of Danyetta and her daughter which belonged to Koepp
DNA found on the clothing of Koepp which belonged to the victims
DNA testing is so accurate that the chances of convicting the wrong man are minute. The possibility of the DNA found under the nails of the victims not belonging to James Koepp are 1 in 7 quadrillion making it definitely Koepp’s DNA. In police interviews James Keopp claimed he in fact did not intent to kill anyone.
DNA forensic testing outside the sphere of criminal investigations
Our DNA is not only present in our blood. DNA is present in every cell in our body (though not present in red blood cells). We inevitably have traces of DNA in our saliva, after using a drinking glass, in faeces, mucus in tissues; these are just some of the possible samples. Thus, we can say that many times we leave DNA samples without realizing or thinking about it.
Paternity DNA testing, relationship DNA testing and a number of other tests offered by DNA testing companies can test a number of DNA samples in a way that replicates the techniques used in forensic investigations. These samples are often called forensic DNA samples. Many times people doing such tests may wish to send in a sample for their paternity test by using a semen DNA sample or perhaps some nail clippings that have been left lying around.
DNA samples in such cases are usually used when a party who is taking part in the test is unavailable for testing. In such cases, one must be aware of laws in certain countries which may limit how DNA is used. The DNA testing company chosen by those interested in the test will provide all the necessary information regarding the issue.