The Department of Justice says, "States began passing laws requiring offenders convicted of certain offenses to provide DNA samples. " That DNA evidence can help convict someone of a crime and it helps to uncover more things about the crime itself. Investigators have been using forensic science to help them solve cases since before the 90 's, mostly fingerprints that were found at the crime scenes and on the victims (O 'Brien). DNA evidence has solved countless cases including ones that happened over a prolonged period of time because of the technological advancements there is
The leader of this group, named Deirdre, said that scanning extra objects for DNA is important, ”When I talked to DNA experts that they were saying, ‘Yeah, I mean, if you swab that and get some skin cells or saliva and it’s just random, you get no hit on anybody, well then it neither here nor there.’ But they were saying, ‘but if put it in and you get a hit on a serial killer… well now you got enough to charge and convict somebody.’ So what you call relevant and irrelevant you can only do once you have a test result” (111). Deirdre likes to test anything that could possibly lead them to another suspect in the crime. Not everyone in the detective business is, however, not like her.
Alan Crotzer—DNA Exoneration In the United States, there have been a total of 321 DNA exonerations to date, with twenty of these exonerees having served time on death row (“The Innocence Project,” n.d.). Alan Crotzer was not one of these twenty, however he was sentenced to 130 years in prison for a crime that he didn’t commit. Charged and convicted of sexual battery, kidnapping, burglary, aggravated assault, robbery, and attempted robbery, it wasn’t until 24.5 years later, on January 23, 2006, that Crotzer was released from prison after post-conviction DNA testing proved his innocence (“The Innocence Project,” n.d.).
What if the DNA was tampered with or contaminated? DNA testing is not always reliable and this issue is evident in a large number of investigations. One well known incident of this occurring is the Josiah Sutton rape case- "In 2004, Josiah Sutton was exonerated after serving four and a half years of a 25-year sentence for a rape he did not commit. Sutton's conviction was the result of a mistaken identification and faulty scientific testing performed by the Houston police laboratory.
The murder of JonBenet Ramsey is a crime that received national attention and was seen on nightly news stations and talk shows across the country. All of this attention made the case extremely controversial (Saferstein, 2015). It is now over twenty years since the murder occurred and the case still remains unsolved. The development of DNA evidence has played a critical role in the course of this arduous investigation (Saferstein, 2015). Crucial mistakes were made from the very start of the investigation by police and then by the district attorney, Mary Lacy (Saferstein, 2015).
The police took hair and saliva samples from Gary in 1987 but unfortunately due to DNA not being well developed yet he was released with no further questioning. (Gish, 2017) The DNA content of biological samples can be quite high depending on the type of sample and how well you acquire them. Depending on local conditions which they were found and especially on the length of time between deposition and collection. Gladly, in this case, the hair and saliva sample which saliva contains 100-1 500 ng/swab and a hair plucked (with root) contains 1-750 ng/root, was well collected and stored, making possible to solve this crime.
Destiny Johnson LSTD 502 Criminal Law January 10, 2016 A. Research Paper Topic: Wrongful Convictions B. Law abiding citizens should not be wrongfully convicted of a crime that they did not commit. Deoxyribonucleic Acid (DNA) was first used to aid a criminal investigation by Professor Jeffreys in 1986 for rapes/murders that occurred in the United Kingdom. The first DNA exoneration took place in 1989. Prior to DNA testing there were hundreds of wrongful convictions.
The one key physical piece of evidence linking Scott Peterson to the murder of Laci is the 6-inch dark strand of hair found wrapped around pliers on Scott’s fishing boat(Vries, 2003). Ultimately, the discipline that led to the death sentencing of Scott Peterson was Mitochondrial DNA determined to be that of Laci Peterson in the dark hair strands on his pliers(Vries, 2003). Mitochondrial DNA testing has been around many years dating back to its use of identifying the causalities of the Vietnam War and victims of the 9/11 attacks(Vries, 2003). There have been admissions of computer glitches and routine failure of lab equipment in the past, but this method is widely accepted across the nation as admissible evidence(Vries, 2003). Mitochondrial DNA testing cannot particularly identify someone, but it can statistically conclude when compared to a relative’s DNA a likely match(Vries, 2003).
One of the most accurate methods of connecting a suspect with a crime is through the use of DNA analysis. Even if no fingerprints are left behind at a robbery, for instance, a single strand of hair or skin cell from the thief can be used to positively identify a suspect. Conversely, if a suspect’s DNA does not match samples procured from a crime scene, the use of so-called “genetic fingerprinting” can exonerate, or clear, them. Concern over the issue of wrongful convictions, coupled with a sense of greater trust in DNA analysis over other, more conventional methods of prosecution, such as eyewitness testimony, has led some to call for mandatory DNA testing before any person begins serving a sentence for a serious crime, as well as
But in Adnan Syed case this was not done. If the DNA test was
In King, Justice Kennedy referred to the invention of DNA technology as “one of the most significant scientific advancements of our era.” This statement has been criticized, but the impact of DNA technology has been significant. Currently, forensic analysts can use “junk” DNA to identify a person with near certainty. Law enforcement can collect a person’s DNA through saliva. The sample is then uploaded to CODIS, a national network of DNA databases.
Today, practical methods of using fingerprinting are extremely wide. In 1995, the size of the FBI fingerprint card archive contained over 200 million items, and archive size was increasing at the rate of 30,000 to 50,000 new cards per day [2]. Forensic science was the very first and most important area of its application, which still remains. The rapid development of computer technology has made it possible to create such fingerprint scanners that can be installed on laptops, cell phones, flash drives,
D Assessment DNA technology Forensic testing 24.11.2014 Marius Martinsen 10D Introduction: I have chosen to investigate Forensic testing, it is also known as DNA profiling or genetic fingerprinting. During this essay I will discuss what the disadvantages and what the advantages of forensic testing are. I will also talk about how forensic testing is carried out. Forensic testing is used to identify an individual by using the DNA sequences of that person.
Although, in our lab report, suspect ones DNA matched the crime scene when cut with enzyme one, this can be explained by how closely related the two suspects are. Therefore two enzymes were used to cut the DNA; the suspect has to match both. Moreover, the limitation to DNA fingerprinting is, if a person were to have an identical twin. This is because identical twins have the same DNA because they come from the same egg. If a suspect’s DNA matched that of the one being tested, and they had an identical twin, a farther investigation would need to be done.
DNA in forensic science The majority of cells making up the human body are diploid cells carrying identical DNA, with the exception of haploid gametes and red blood cells. Several types of biological evidence such as blood and hair are commonly used in forensic science, which is the scientific study of evidence for crime scene investigations and other legal matters. Forensic science is used for the purpose of DNA analysis, this is the analysis of DNA samples to determine if it came from a particular individual. DNA analysis is done by obtaining DNA samples from an individual; next, a large sample of DNA is produced from amplified selected sequences from the DNA collected.