At a crime scene there may be a lot DNA evidence left behind or none. DNA can identify victims and suspects. It can help solve cold case and give new leads to other cases. DNA is also use to determine kinship in a missing person case. It can also help exonerate someone from a crime that they were convicted of. When handling DNA such as blood at a crime scene it is important that it is properly documented, photographed, collected and stored. Besides blood, DNA can include: body fluid, hair and skin. Such DNA can be matched to an individual.
DNA is the acronym for Deoxyribonucleic acid. According to Campbell Essential Biology with Physiology, “The word nucleic is referring to “DNA location in the nuclei of eukaryotic cell.” (Page49). “DNA is genetic material that humans and other organisms inherit from their parents which consists of gain molecules” (Page 48). The shape of DNA is a double helix. Some would say it looks like a twisted ladder. “The double helix has four bases; (A) Adenine, (C) Cytosine, (G) Guanine and (T) Tyhmine. The bases have to be properly linked to their pair or else there will be a mutation in the gene. The following are the base pairs that bind:”Adenine with Tyhmine and Cystosine with Guanine” (Page 49).
DNA testing began in the mid 1980’s. In the online article, DNA Factors states: Ever since the start of DNA testing in 1985, biological material has been a reliable physical evidence to help solve crimes (Williams). DNA plays a key role in helping solve cases at a crime. In 1987, Tommie Lee Andrews became the first person in the United Sates to be convicted of a crime as the result of DNA evidence (Williams). Tommie Lee Andrews was a rapist in Florida (Williams). After, the conviction of another case was solved by DNA evidence. In 1988, a man from Virginia which was called the “South Side Strangle” was convicted after DNA left at the several scenes linked him to murders and rapes near Richmond (William). This goes to show that DNA is a great way to link a suspect to a crime. It is hard to deny being at a crime scene if your DNA is located there when they said they never been to the location or never came in contact with the victim. In its early ages DNA helped save many people lives by capturing suspects.
Since the mid 1980’s DNA technology has made many improvements. According an article written by The National Institute of Justice, “The CODIS is a computer network that connects forensic DNA laboratories at the local, state and national levels together” (Forensic Sciences). It is ran by the FBI. The CODIS Unit manages the Combined DNA Index System. The following is how the CODIS work’s: When there is blood evidence at a crime scene it is collected and entered into the system. The system then runs the entry through the database.(Forensic Sciences). There are blood samples from every convicted person in the database. Also registered sex offend are entered into the database. This is a great tool to help solve crimes the only downfall to it, is that if the suspect blood sample is not in the database it will not find a match. Not only can CODIS help with solving crimes it can also help aide in finding missing persons (Forensic Sciences). The missing person’s index contains many DNA profiles of unidentified remains and the DNA profiles of the relatives of the missing person. Making a DNA profile of unidentified remains but it also helps out the search more when they have DNA profiles on the relatives. This way the might get a hit in by having a larger blood group pool to help identify the person.
Another program that plays a vital role in the criminal justice system that help provides investigator with physical evidence is the National Institute of Justice. The mission statement of the NIJ is to ”provide objective and independent knowledge and tools to reduce crime and promote justice, particularly at the state and local levels” (National Institute of Justice). The NIJ has six operating offices. The following of the list of the offices; “Office of Research and Evaluation, office of Science and Technology, office of investigative and forensic sciences, office of research partnerships, office of operation and the office of communications”(National Institute of Justice). All of these offices make the NIJ a strong justice system that can meet the different needs other criminal justice departments.
There are four major blood groups. According to the American Red cross, “these different groups are determined by the absence or presence of two antigens” (American Red Cross). The two antigens are A and B which are on the surface of red blood cells. The following are the four different blood types: “Group A, Group B, Group AB and Group O” (American Red Cross). One who has “Group A blood type only have the A antigen on red blood cells and B antibody in the plasma” (American Red Cross).One who was “ Group B has only the B antigen on red blood cells and A antibody in the plasma” (American Red Cross). One who has “Group AB blood type has both A and antigens on red blood cell and A antibody in the plasma” (American Red Cross). Last but not least, “Group O has neither A or B antigens on red blood cells but both A and B antibody are in the plasma” (American Red Cross).
Everyone has a different DNA sequence except identical twins. One might have the same blood type as someone but their blood sequences are different. Your blood type can be the same or different from your parents. Also your parents might not have the same blood types as each other. To find out your blood type one can ask their physician to run a blood test on them.
There is several way that a person can be identify by the DNA they leave at a crime scene. “When one DNA is ran through the database it is looking for a few genetic markers to find the perfect match” (Evett,Weir). Everyone have different genetic markers in their blood that is unique to only them. Forensic DNA Analysis article states that,” In the United States many times only thirteen markers are need for a match but some have been match by only using six markers (Evett,Weir).One would think that your parents will have of the same markers the can also identify them as a suspect but there is a about three million difference between each person blood(Evett,Weir).
There are different techniques that can be used in DNA forensic investigations. The following are a list of the diff erent techniques according to the U.S. Department of Energy Genome Program “Restriction Fragment Length Polymorphism (RFLP), Polymerase chain reaction (PCR) Analysis, Short tandem repeat(STR) Analysis, Mitochondrial DNA analysis (mtDNA) and last but not least the Y-Chromosome Analysis”(DNA Factor). The U.S. Department of Energy Genome Program states, “RFLP digest a DNA sample in in an enzyme RELP was the first type of techniques use but others or chosen over it now because it requires a large sample. Some of the other techniques requires very little DNA and thus is used more often.
There are several steps that should be done to process a crime scene. The following are the steps that need to taken: properly document, collect, photograph and store the evidence. Preserving the DNA evidence at a crime scene plays a huge role in being able to conduct DNA trace. You might not find a suspect right away but years later one could solve the case with DNA evidence, that was collect years ago. Following the chain of custody when dealing with any type of evidence is another aspect of preserving DNA evidence and or any type of evidence. Wearing clean gloves and changing them when needed is one of the proper ways collect evidence and avoid cross contamination. One should change their gloves often, do not transfer trace evidence other items: ex. blood on a shirt. Collect a swab of the blood stain. “If you had a liquid blood sample it should be stored in a collection tube and refrigerate until it can be processed” and later entered in the CODIS” (Crime Scene Forensics, LLC). By following the proper steps and methods in collection can insure that evidence will still be valuable years later.
When handling (DNA) blood at a crime scene there is steps in collecting bloody items. If there is blood on any clothing is cloth material it should be air dry before packing (Crime Scene Forensics, LLC). If the blood is not fully dried before its package it can transfer onto parts that are not bloody and cause contamination. Also packaging wet blood can cause bugs to infect and possibly ruin the item of evidence.
One lab should have a special room just for drying wet or bloody items of evidence. The bloody evidence should be taken back to your crime lab and store it and a drying room and allow it to fully dry. “It should be packed in paper bag not plastic” (Crime Scene Forensics, LLC). Plastic bag will create moister and can mostly cause contamination.
The fourth amendment of the United States Constitution states “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized” according to Findlaw. (Find a lawyer). This means that the police cannot take a person’s DNA without probable cause. A DUI is an example where the police cannot take your DNA.
There are advantages and disadvantages when it comes to taking DNA on arrestee. There are more disadvantages then advantages. In the online article, Does Taking DNA of Arrestees Violate the 4th Amendment states, one advantage: “Usually when someone commits a major crime they are people who have committed other offense too. By having their DNA banked it can make it a lot easier to identify suspects” (DNA Forensics). A disadvantage is, “If someone DNA is already in the DNA database they could be identified as a match or partial matches to DNA found a crime scenes” (DNA Forensics). The bad part is, it could happen to innocent people. If they have been at a crime scene earlier or had similar DNA profile to the actual criminal (DNA Forensics).This is an understandable concern, with DNA marker one could be cleared of the crime. Another thing that worry people is that there person information will be available to anyone. The DNA database it secured against hackers.
There is a legislation that allows law enforcements to take DNA from an arrestee. “Out of 50 states there is 21 states that have passed legislation to make is legal for law enforcements to swipe the inside of an arrestee’s inner check for DNA” (DNA Forensics). By doing this there is more DNA being entered into the DNA database and this could possibly solve more crimes. This legislation is helping solving crimes. Some see it as way for law enforcements to violate a person’s right. Not only is collection arrestee’s DNA a way to help aide solve crime but it can also protect to help Society. It will take criminal off the streets and prevent them from harming innocent people.
DNA can be found at all types of crimes such as, rape, robbery, murder, carjacking and burglary ect. Unfortunately, some crimes have a statute of limitation. Sometime DNA can help link a suspect to a crime but they cannot be charge for it because the statute of limitation has ran out for that crime. “A statute of limitations is a law which places a time limit on pursuing a legal remedy in relation to wrongful conduct” (limition). Murder does not have a statute of limitation.
DNA can not only help solve crime but it can free innocence people who were wrongfully convicted. There are many organization that help free the innocent but a well-known organization is known as “The innocent Project”. It was founded in 1992 by Barry C. Scheck and Peter J. Neufeld at the Benjamin N. Cardozo School of Law at Yeshiva University to assist prisoners who could be proven innocent through DNA testing (incconet). This organization has given back so many people their lives.
DNA plays a huge role in helping free innocent people from jail. “The Innocence Project is a national litigation and public policy organization dedicated to exonerating wrongfully convicted individuals through DNA testing and reforming the criminal justice system to prevent future in justices” ( innoncee). The program helps release the Innocent from jail. It is not fair that some people have to spend 30 years in jail before they are proven not guilty through DNA testing. Most would agree that it is better for one guilty person to walk free than an innocent person suffers in jail.
There are many factors that come into play of why people are wrongly convicted such as; “eyewitness misidentification, unreliable or improper forensic science, false confessions, informants falsely testing in court, government misconduct and bad lawyering” (The Innocence Project). Although the criminal justice system is well designed, it is not perfect. There are measurements put in place to make sure that things like the ones listed above do not happen. The following are facts and statistics of the following factors listed above:
In not all cases but sometime the evidence is tamper with or altered. “Forensic analysts have fabricated results or engaged in other misconduct” (The Innocence Project). This is rare but sometimes people with power do the wrong things to solve cases. They forget to maintain their integrity.
When handling DNA evidence it important not to break the chain of custody and avoid contamination. “The cases of wrongful convictions uncovered by DNA testing are filled with evidence of negligence, fraud or misconduct by prosecutors or police departments” (The Innocence Project).Sometime a police officer might want to be the hero and solve the cases so bad that they lie or make up evidence.
The case of William Dillon was help solved by the Innocent Project. The case was solved through DNA testing. William Dillon was freed from a Florida prison in November 2008 after serving nearly 27 years for a murder DNA proves he didn’t commit. “He was wrongfully convicted in 1981 based on a questionable eyewitness identification, unreliable testimony from the handler of a scent-tracking dog and testimony from a jailhouse informant” (The Innocence Project). All chargers were drooped against William in December 2008.
DNA evidence plays a very important role when solving cases. It not only helps save people lives from murders; by collecting their DNA upon arrest. DNA can also free the innocent. DNA evidence can range from blood to semen. When properly collected and store it can last for years. The collection of DNA is not a violation of the fourth amendment but a tool to help build the DNA database. Crimes all over the world are being solved my DNA and other trace evidence.
