The Correlation between DNA and criminal investigation in a modern society

LFCC SUMMER CHM 101 Genevieve Blodgett Final Research Paper APA

DNA can be used in a variety of ways. Identifying a victim is only the beginning. Even the smallest sample of hair can convict a perpetrator, or exonerate one that has been falsely accused. Oftentimes, in cases of rape and sexual assault, the victim may not have been able to remember many details of the assailant. He may have been masked, or the trauma was too much to bear and a survival instinct kicked in. Collecting DNA from semen and body hair is often a surefire way to correctly identify a rapist after an attack. DNA can also be used to exonerate a victim of wrongful accusations. IF DNA is collected at a crime scene, and does not match the accused, this can be a way to eliminate suspects and help detectives further narrow down the pool of subjects.

All of the different body cells except for completely mature red blood cells contain healthy DNA samples. Anything from semen, skin flakes, saliva, and even sweat can be profiled. DNA is found in two places: the nucleus and mitochondria outside the nucleus. There are 2 different types of DNA in the nucleus; autosomal and sex-determining. Both of these are equally unique, but no two people have the same autosomal DNA except for twins. Autosomal DNA is used in most criminal cases because it is unique. Because of the sex-determining Y and X chromosomes, we can automatically eliminate one gender or the other solely based upon this observation. An STR test is run to determine the sex of the assailant. If the perpetrator, the test will be positive for the Y chromosome, as it is the one passed down from the father and ultimately decides if the fetus is female or male.

Mitochondrial DNA is inherited from the mother. This is different because all persons related to the other could have very similar DNA. It varies a little bit, but not for the most part, it is nearly identical. This can cause some confusion when testing family members because the similarities are close enough to cause unrest with scientists attempting to rule out suspects. Mitochondrial DNA is often used in missing person cases as well as unidentified remains This is caused by its ability to withstand time, and not deteriorate with the elements. It does not degrade very quickly and can still be used after hundreds of years, even thousands. Autosomal DNA deteriorates with the living cells.

There are many differentiation features in different DNA samples, such as race, health, and sex. Each of these can eliminate the suspect pool and make the process of finding the victim and/or perpetrator so much easier. Oftentimes, even the smallest trace of biological material can be key. DNA can be extracted from a single hair left in a blanket or even 2 people of blood. There is a way of separating different DNAs from mixed blood. Finger smears on a window can leave behind skin cells which can be tested as well. This small evidence can be crucial when all hope seems lost. Even with today’s technology, we don’t always have cameras and voice recorders to catch assailants. Being able to test blood for different environmental factors and even observing the blood spatter patterns can tell a lot about a crime scene.

Along with the scientific uses of DNA evidence, there is a very strict process before it may be admitted into a court of Law. The DNA must be properly cataloged and tracked. There are several factors taken into account when collecting DNA samples from a crime scene. Pictures must be taken and measurements made are necessary, environmental factors, such as temperature, humidity, air pressure must also be recorded, as they can have an effect on the quality of the biological sample. It must also be lawfully obtained. Sometimes a warrant will be needed in order to demand a DNA test. Unless the evidence is obtained lawfully, it may not be used as viable evidence.

Testing Labs must also be kept up to federal standards. There are all kinds of regulations, such as location and privacy that must be upheld. DNA testing is also a very specific profession, so only those with the proper credentials may be allowed to testify in court. Even though DNA is unique in itself, mistakes can still be made. Criminals have gone to jail before because of mixed-up samples and human error, so specifics and preciseness are crucial to this line of work. Labs are subject to inspection and must be able to keep up with the advancements in technology, as well as the ability to adapt to difficult situations. Working under pressure is common in the labs, there are many cases where there is a missing person and a life on the line. These scientists are relied on to give closure and justice to so many people every day.

As time goes on and we move forward as a society, there will always be advances in technology. A huge reason that DNA in criminal investigation is so common now is the availability of knowledge and resources. In order to preserve these advancements and allow new discoveries to be made, we have to stick to the facts. Learning more and more every day through experimentation and observation is the only way that these methods will stay up to date and accurate. Specialization scientists and doctors often work together on a case, as many different talents are needed. Even though we may have technology doing more and more of the work, we will always need human intelligence to maintain it and make sure that everything is running smoothly.

Along with DAN testing, DNA collection and sampling are also starting to become more prevalent. With all of the DNA testing kits that allow people to see their ancestry at home, these companies have personal DNA. This can be good and bad at the same time. There is the issue of personal privacy and what companies do with the DNA. They have a responsibility to protect their databases and protect their customers’ personal information. At the same time, if someone chooses to send their DNA off to n of these testing facilities, they run the risk of their data being breached. There is a national database with DNA samples from almost everyone who has been through the judicial system, whether criminally or just sampled as a formality in a criminal case.

The national DNA database is called CODIS (Combined DNA Input System). This houses all DNA samples from anyone who has been tested by the government, from criminals to law enforcement to government officials. One sample’s DNA code can be uploaded and searched through the database, and could potentially be matched with an identity. In some cases, there will be a match to a family member, which is almost just as good because oftentimes, the family can be tracked down. This also has repercussions, it can put the spotlight on those who want their privacy and can often result in familial issues and breakage of bonds, even though the accusation could be completely false.

Wrongful convictions are a huge source of contempt these days. Even though DNA evidence is very reliable, it can be false. Unfortunately, there have been cases where an incomplete DNA sample was used to convict a person, just based on one component. Sometimes DNA profiles/samples can be incomplete, so scientists are only able to interpret certain parts. So if we are only able to see that the DNA profile belongs to a man who is tall and has brown hair, sometimes investigators and prosecutors will jump to conclusions. This is why we must continue to regulate the science of DNA profiling so that we can completely eliminate false convictions.

DNA and Criminal investigation have come a long way since 1986 when it was first used to bring those two girls from small-town America, justice. Allowing scientists and law enforcement to work together on this revolutionary discovery has changed countless lives, as well as let many others have closure. Families of Victims can rest easily knowing that justice was served. Parents of missing children don’t have to spend years wandering in agony about the fate of their beloved child. Now, we must make sure that we continue to advance in technology and knowledge, earning as much as possible and putting that knowledge to good use. DNA evidence has been vastly beneficial to our society, giving closure to victims and their families, as well as correctly identifying perpetrators in a timely manner.


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