DNA Criminal Evidence - Assignment Example

It is a basic rule of evidence that when the terms of an agreement have reduced to writing, it is considered as containing all the terms agreed upon, and there can be, as between the parties, no evidence of such term other than the contents of the written agreement per se. A classic example of documentary evidence is a contract. Parol or oral evidence refers to the testimony of a witness made before the judicial court. An example of this type of evidence is the testimony of the victim in a rape case.

One of the popular cases in Canada where DNA testing was allegedly used was the case of Dr. John Schneeberger. The latter is a doctor who raped one of his sedated patients in 1992 and intentionally left semen on the victim's underwear. The police immediately got blood samples from Schneeberger's blood and compared the same DNA to the DNA from the semen found at the crime scene on three different occasions. However, the matching proved to be negative. It was found out later on through other evidence that Dr.

John Schneeberger inserted a Penrose drain into his own arm through surgery and then filled the same with foreign blood and anticoagulants. Anticoagulant is a type of drug that prevents the clotting of the blood while a Penrose drain, according to Wikipedia, is a surgical device placed in a wound to drain and prevent the build-up of fluid. This, in turn, resulted in the degradation of the value of DNA evidence in criminal cases since DNA samples may be faked and planted, just like in Schneeberger's case.

In this case, the DNA sample, although previously admitted by the court, failed to prove the suspicions earlier made by the police authorities.DNA evidence is real or objects evidence since it is a shred of material evidence that is addressed directly to the senses of the court. Although logically, judges and justices may not appreciate its value without the corresponding interpretation and testimony of scientists expert in the field, it can stand alone in court as evidence and therefore maintains its classification as a shred of real or objective evidence.

In most states in the United States, DNA evidence is admissible in court even without the corresponding expert testimony. However, in some jurisdictions, the expert testimony plays a big role in determining the admissibility of DNA as evidence.Personally, I do not agree with the use of DNA as evidence in proving the guilt or innocence of an accused. There are relevant scientific studies where it was concluded that DNA testing is not 100% perfect although the ratio of its reliability reaches one is to 5 million.

Criminal prosecution is totally different from civil ones. It is the life and liberty of the accused which is at stake. It has been said that it is better to leave a criminal free rather than punish an innocent man. In this case, no matter how small the percentage of the probable mistake may be committed in the DNA testing and studies, the same cannot justify prosecution and persecution of innocent people. It is totally different however in using DNA testing as a means of proving paternity, for example, as the same is civil in nature.