DNA test results can be used in many different cases where it is important to discover the identity of a person who has committed some type of act. This could be a serious act of crime such as rape or murder, or the simple act of fathering a child. The person committing the act will invariably leave some degree of evidence of their identity in the form of DNA, and this can be used to both exonerate innocent suspects and build a case against guilty ones. Whether this DNA can be successfully used to determine the truth depends entirely on the purity of the samples obtained.
DNA testing was discovered and developed in England during the 1980s, and scientists around the world were quick to realize the possibilities and implications. The technique was quickly made commercially available, and it has been used ever since to determine the outcome of both civil and criminal cases. The technique has even been used to shed new light on cases which are virtually a century old, often by taking DNA samples from living relatives.
It is possible to use DNA profiling for identification because certain strands of DNA within each individual are unique. This happens because the DNA is transferred from both parents to the child. This means that using DNA in paternity cases is especially appropriate and accurate, and there are many companies offering this type of test as a private service. In criminal cases, the degree of accuracy depends entirely on the purity of the samples obtained, and it is in these cases where the strictest degree of proof needs to be obtained.
Potential problems with DNA profiling occur when samples can become contaminated, or when they degrade over time. Contamination is possible at any stage of the analysis, including when samples are not stored correctly. There have even been instances where swabs used to extract DNA have been found to have had DNA already on them before they were used, leading to a guaranteed inaccurate result before the testing even started. Degradation has also raised doubt over conclusions drawn concerning old cases where exhibits have deteriorated over time.
The future of using DNA test results to determine case outcomes depends on achieving purity of samples and certainty of procedure. If there is the slightest doubt as to how the samples have been collected or stored, or if the samples have been taken in a way which compromises then right from the start, juries will have enough doubt to totally disregard any conclusions. It is imperative that law enforcement learns from some of the mistakes which have been made in the last thirty years, so that they can achieve the higher detection rates promised by the correct use of DNA test results.