The most powerful criminal justice tool from the past decade has seen great advances – one is deoxyribonucleic acid or DNA. DNA is being used to identify criminals with unbelievable accuracy when biological evidence exists. In fact, by the same time DNA can also be used to clear any doubts and suspects and exonerate persons who has been mistakenly convicted or accused for crimes. Overall we can say that the DNA technology is increasingly vital to ensuring the fairness and accuracy in the criminal justice system.
Some successful stories about use of DNA to solve crimes are already trolling around. In fact from the past few years we can see the use of DNA for solving crimes. In the year 1999, New York authority linked a man through DNA evidence to atleast 22 sexual assaults and robberies that has been spread all over the city. Again in the year 2002, authorities in Philadelphia, Pennsylvania and Fort Collins, Colorado, used this DNA evidence to solve a series of rapes and murder carried out by the same individual. In 2001, DNA evidence provided major changes in a series of crimes which had remained unsolved for years after years despite a large law enforcement task force and lots of investigations.
So, using of DNA in solving different level of crimes is really helpful from those days. DNA is mainly used to solve crimes in 2 different ways. If a suspect is identified, a sample of that suspected person can be compared to the evidence from the crime scene. The comparison result will help to establish the fact that whether the suspect committed the crime or not. But if the suspect has not yet been identified, then the biological evidence from the crime scene can be analyzed first and then compared to the offender profiles in DNA database which is present to the investigation department in order to help identifying the perpetrator.
For example, suppose a man was convicted for sexual assault. Now at the time of his conviction, he need to provide the sample of his DNA, and the resulting DNA sample profile was entered into a DNA database. Now, several years later, if another sexual assault occurs, then the examiner who is working with the victim was able to obtain biological evidence from the rape and then the evidence has been analyzed and the result will be cross checked with the DNA database and it can happen that a match has been found with the previous man’s DNA profile. He was then apprehended, tried and sentenced for his second crime. In such hypothetical case and taking such decision, another crime by the same person can be prevented during the period of his incarceration.
DNA evidence is linked to the DNA offender profile which is present in the DNA databases. In the year 1980s, the federal government has laid the groundwork for a system of national, state as well as local DNA databases for the storage and exchange of DNA profiles. This is system is known as CODIS (Combined DNA Index System) which is actually maintaining the DNA profiles obtain under the federal, state and local systems in a set of databases that are available to the law enforcement agencies across the country for solution of the crime evidence purposes. The purpose and work of CODIS is mainly to compare the crime scene evidence to the database of DNA profiles obtained from convicted offenders. CODIS can also link the DNA evidence which is obtained from different crime scenes so that serial criminals can be identified easily.
Thus to take the advantage of the investigation potentiality of CODIS, states began to passing the laws that could require for offenders convicted of certain offenses to provide DNA samples in the late 1980s and early 1990s. Currently different states around the world as well as the federal government have the laws of requiring that DNA samples to be collected from some categories of offenders.
If DNA can be used to its full potential, then this evidence can be helpful for solving crimes and even able to prevent any serious violent crimes. After all such issues, the current federal and state DNA collection and analysis system software needs some improvement:
1. There are so many cases, where public crime labs are overwhelmed with backlogs of unanalyzed DNA samples.
2. These labs may not have sufficient equipment t handle the increasing influx of DNA samples for evidences. The problems of lack of updated technology result in significant delays in the administration of justice.
3. More research is required to develop faster methods of analyzing DNA samples.
4. In the criminal justice system, professional and properly trained assistance is requiring in order to ensure the optimal use of DNA evidence to solve and assist crimes.
In the pop culture, DNA is often portrayed as the magical piece of evidence which can link the perpetrators to crimes and exonerates the innocent. But in real life, taking samples of DNA more than one person and checking everything can be tough. Over the last few decade, forensic scientists have realize that traditional methods for interpreting mix samples can be less reliable that previously thought.
Thus, today lots of companies are selling a solution of this: software that claims to interpret mixed DNA with a high degree of accuracy. These companies have researched a lot and point to several peer reviewed studies that describe the underlying mathematical concepts of their programs and as a result of mock testing through which they can correctly interpreted known samples.
DNA Software System
There are few draw backs of such software as per the some well known persons. However, five crime labs in the U.S. use TrueAllele software and hardware, according to Perlin. Other agencies may also prefer STRmix, including the California Department justice which found that it had the ability of producing more reproducible and sensitive results with fewer reanalysis as compared to TruAllele. STRmix has already used for lots of cases that gave great results. In fact a trio of New Zealand and Australian forensic scientists began to start working on STRmix around the year 2009. They also published its mathematical model in scientific journals. Developer John Buckleton told that the source code is actually available when requested under appropriate circumstances and supervision conditions but did not mention those conditions. In fact more than 50 customers including FBI and U.S. Army Criminal Investigation Laboratory are using this STRmix software. In fact according to Haned it is not required to be open sourced to become good software. But it could be difficult to interact with other scientists when there is any layer of secrecy.
However, still now everyone thinks that raw code is helpful. Public believes that DNA is largely infallible. Cybergenetics and so many other similar companies are also believed in it.