Does DNA profiling in its current state offer foolproof identification? What needs to be in place for it to be error-free? Should all incarcerated criminals be forced to give samples? Should convicted juveniles? Should the general public be required to give a DNA sample?
The pros of DNA profiling are that it can be used to quickly eliminate a suspect, saving time in searches for perpetrators. And it can provide compelling evidence to support a conviction and, most importantly, reduce the chances of a wrongful conviction.
Another pro os DNA profiling is paternity testing, usually to determine fatherhood of a child when this is disputed. It may also be used in helping to identify whether objects have been handled by, or belonged to, a missing person. Also in rape cases, there is no need for a victim to testify about whether a sexual act took place. There's no question, typically, about mistaken identity being the problem, because DNA from a semen sample can be used to link a suspect to that semen sample. In fact, it has been useful for excluding innocent people. The FBI says that, of many test results, that they could never exclude with standard blood markers, nearly a third of those people are exonerated immediately upon DNA testing. Many rapists, because of this, now plead guilty.
The cons of DNA profiling are the accuracy of DNA profiling in matching to people depends on the technique used and particularly the number of loci checked. While this is getting better so the chances of a false match are very small, the courts have not yet accepted it as absolute proof of identity.
If a particular exhibit is handled by a number of people the DNA profiling results indicate a mixture; so interpretation is not always straightforward.
Also how a person process's DNA samples , if they do a messy job and the ink is smeared it would not be of use in court.
DNA in it's current state doesn't offer foolproof identification because, people that process it can make mistakes, it can become contaminated, controversy that has arisen is about how to interpret a match. What frequency should you put on it? How rare is a pattern? How odd is a match? And for this, the controversy is a technical one and a complex one, but it has to do with the fact that the frequency of the different DNA patterns of different genes vary across the population. This is actually a blood group frequency distribution. Similar things are known for other types of DNA differences. And so there has been active controversy about exactly what weight we...