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DNA Evidence, Cases of Exoneration

DNA Evidence, Cases of Exoneration

When available and properly utilized, DNA is a powerful component of the forensic science and criminal justice systems; it can link seemingly unrelated crimes, resolve cold cases, track violent offenders both in and out of the penal system, solve crimes which would have been previously unsolvable, and prevent innocent people from going to prison. Currently, DNA is also being used to exonerate the innocent. Many people who were convicted of violent crimes and sentenced to lengthy periods in prison have continuously stated their innocence. DNA technology now makes it possible, in some cases, to prove or disprove their claims.

At present, there are more than 30 Innocence Projects headquartered at law and journalism schools across the United States, the goals of which are to overturn cases based on the introduction of compelling new evidence (frequently DNA-related). Attorney Barry Scheck started the first Innocence Project in New York in 1992; his goal was to be "the last word" for impoverished clients who maintained their innocence but had run out of other legal options. As of early 2005, nearly 160 people have been exonerated by the work of these groups. In addition to their goal of exonerating the wrongfully convicted, the Innocence Project is working to require states to pass legislation mandating that case evidence be preserved, and DNA testing be made readily available to those accused of crimes.

A parallel project was commissioned by the National Institutes of Justice and carried out by the Institute for Law and Justice in Alexandria, Virginia, in 1995. This project involved the study of cases in which post-conviction DNA analysis led to exoneration, as well as an in-depth investigation of DNA laboratories and testing processes. In her commentary on the release of the original report in 1996, former United States Attorney General Janet Reno said, "...DNA aids the search for truth by exonerating the innocent. The criminal justice system is not infallible, and this report documents cases in which the search for truth took a tortuous [twisting] path. With the exception of one young man of limited mental capacity, who pleaded guilty, the individuals whose stories are told in the report were convicted after jury trials and were sentenced to long prison terms. They successfully challenged their convictions, using DNA tests on existing evidence. They had served, on average, 7 years in prison."

DNA testing can be done on blood , semen , saliva , skin and tissue (buccal cells, or inner cheek scrapings, are frequently used), and hair. In one of the earlier recorded cases of the forensic use of DNA technology, in 1986 police in the United Kingdom requested that Alec Jeffreys of Leicester University verify the confession of a suspect in a case involving two rape-murders. DNA testing exonerated the suspect.

In 1987, Robert Melias was the first person in the United Kingdom to be convicted of a crime (rape) on the basis of DNA evidence. Also in 1987, one of the first uses of DNA technology to obtain a criminal conviction was reported in the United States; Tommy Lee Andrews was convicted of rape as a result of a DNA match between his blood sample and semen found in a victim.

One of the earliest recorded cases of DNA exoneration in the United States was that of Gary Dotson. On July 9, 1977, as she was walking home from work, the complainant alleged that she was abducted, forced into the back seat of a car, raped, assaulted, and pushed from the car onto the street. In July 1979, Gary Dotson was convicted of aggravated kidnapping and rape, and sentenced to 2550 years in prison. The prosecution's evidence presented at trial was a police-drawn composite sketch of the defendant, with which the complainant had assisted; results of the victim's identification of Dotson from a book of mug shots and from a police line-up; testimony that a pubic hair removed from the victim's underwear was dissimilar to her own and similar to Dotson's; and the state serologist's report that semen on the woman's underwear came from a Type-B secretor (an individual who secretes the ABH antigens of the ABO blood group in saliva, semen, vaginal, and other bodily fluids ), and that Dotson was a Type-B secretor. In 1985, the victim recanted her testimony and stated that it had been a fabrication to cover up a sexual encounter with her boyfriend. Dotson's attorneys contended that this recantation constituted grounds to vacate the original conviction. The judge hearing the motion (the same judge who presided over the original trial) refused to grant a new trial, because he felt that the original testimony was more compelling than the recantation. In 1988, Dotson's new attorney (Dotson was released from prison in 1985, and was arrested several subsequent times for other infractions) had DNA tests conducted by Jeffreys of the United Kingdom and by Forensic Sciences Associates in California. These tests did not exist at the time of the original rape conviction. The DNA results indicated that the semen stains on the alleged victim's underwear could not have come from Gary Dotson, but could have come from her (alleged victim's) boyfriend. The chief judge of Cook County (Illinois) Criminal Court ruled that Dotson was entitled to a new trial. The State Attorney's office decided not to prosecute because of the DNA test results and the lack of credibility of the alleged victim. Dotson's conviction was overturned on August 14, 1989, after Dotson served eight years in prison as a result of the wrongful conviction.

Edward Blake, a noted forensic scientist from northern California, was the first to work with PCR (polymerase chain reaction) , which, in 1985, revolutionized the process of DNA testing. According to Blake, DNA testing as it is now done, strongly aids in the corroboration of the facts of a case, and the credibility of DNA evidence lies not just in the act of analysis, but also in the manner in which biological samples are collected, stored, processed, and transported. If there are any flaws in the process, it calls the final results of the DNA analysis into question.

One of the cases of exoneration to which Blake often refers is that of Earl Washington. Washington was a mildly retarded African-American farm hand from rural Virginia, who was convicted of rape and murder , and sentenced to die in the electric chair. In the spring of 1983, Washington had spent an evening drinking with friends, and got into a fight with his brother over a girl. The intoxicated Washington, angry and deeply distressed, ran next door to a neighbor's house to steal a gun with which to challenge his brother. When the elderly female neighbor attempted to prevent him from taking the gun, Washington hit her with a chair, took the gun, and ran back to his house (where he eventually shot his brother in the foot). When he was arrested soon after, he immediately confessed to shooting his brother and assaulting the neighbor. The police also questioned Washington about a number of unsolved crimes, including three rapes; he confessed to all of them. Next, the police questioned him about the rape and murder of Rebecca Williams, a 19-year old Caucasian mother of three small children. By that point, Washington was in tears, and he confessed to her rape and murder as well. The charges for the first three rapes were all dismissed when the victims came in and stated that Earl Washington was not the perpetrator. However, he was charged with capital murder in the Williams case, as there was no available witness. A primarily Caucasian jury heard Washington's case at trial; he was convicted after only 50 minutes of deliberation. An hour and a half later, the same jury recommended the death penalty.

The Virginia Supreme Court denied Earl Washington's appeal, and an execution date was set. Washington decided not to pursue the appeals process further, as he was not able to represent himself, as required, in a Habeas Corpus petition. In order to represent himself, he would have had to read the entire trial transcript, do his own research, write his own legal brief, and then represent himself before the hearing judge. A fellow death row inmate, with the help of the NAACP, successfully filed a civil rights suit charging that death row inmates who sought appeals should be entitled to free legal representation, and Washington's execution was stayed nine days before it was scheduled to occur, so that he might have the opportunity to pursue the appeal process. A Virginia defense attorney named Robert Hall took on Earl Washington's case, who argued that his client had been coerced by the police into making false confessions. Hall suggested that Washington had responded to the initial police questioning with answers based on the information supplied in their questions. When asked if the victim was white or black, he responded "black" (she was white); when asked if she was tall or short, he responded "kind of short" (she was tall). When the police asked him how many times he had stabbed her, he stated "once or twice," when she had died of multiple stab wounds. His responses to virtually every question were inaccurate.

When Hall examined the forensic reports, he noted that the genetic markers from the crime scene did not match those of Earl Washington. Even in the face of all of this information, it did not meet the criteria for reasonable doubt, and Washington was again facing the death penalty. As time went on, the hope for overturning Washington's conviction was shifted to the state crime lab and its ability to perform DNA analysis. Ten years after his arrest (1993), DNA testing done on a vaginal swab from Rebecca Williams indicated no link whatsoever to Earl Washington. His attorneys petitioned then-Governor Douglas Wilder for clemency and, on his last day in office, he offered Washington and his lawyers a deal: he could either accept life in prison without parole, or take his chances with the incoming governor George Allen, who would have the authority to sign the death warrant. Washington opted to accept the deal that guaranteed him the ability to continue to live. Seven years later, another round of DNA testing conclusively exonerated him. Virginia Governor Jim Gilmore finally granted Earl Washington a full pardon and he was released from prison in 2001.

The Innocence Projects have encouraged the public to accept that fact that mistakes are made, and innocent people are sometimes convicted and imprisoned. Prosecutors, as well as defense attorneys, have begun to acknowledge a responsibility to find and free those who have been wrongly convicted. Thus far, DNA testing has resulted in thousands of convictions of guilty individuals, and the exoneration of more nearly 160 innocent people.

see also Circumstantial evidence; Composite drawing; DNA fingerprint; DNA sequences, unique; Mitochondrial DNA analysis; Frye standard.

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"DNA Evidence, Cases of Exoneration." World of Forensic Science. . Encyclopedia.com. 29 Jun. 2017 <http://www.encyclopedia.com>.

"DNA Evidence, Cases of Exoneration." World of Forensic Science. . Encyclopedia.com. (June 29, 2017). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/dna-evidence-cases-exoneration

"DNA Evidence, Cases of Exoneration." World of Forensic Science. . Retrieved June 29, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/dna-evidence-cases-exoneration

DNA Evidence, Social Issues

DNA Evidence, Social Issues

The use of DNA evidence is a controversial issue from a social and ethical viewpoint. Although the techniques are widely understood by scientists and criminal investigators, the public in general does not have a deep understanding of the technology. Gone are the days of heated interrogations resulting in guilt or innocence and basic crime scene evidence. Investigations are now much more complex, using DNA evidence and trace samples. DNA databasing as an investigative tool is new (late 1990's), and the actual techniques of molecular biology are fairly recent (late 1970's). Thus, the vast majority of the population has yet to receive education on these topics. Uncertainty accompanies this lack of understanding, which can also be fuelled by sensationalism in news stories and coverage of trials where DNA evidence is utilized.

As with any new technology, a certain amount of speculation accompanies DNA profiling and databasing. Many people are concerned it is a fine line between developing a DNA database and violating civil liberties. DNA contains a wealth of information about not only an individual, but also can give information about family and ethnic background. Inappropriate use of DNA profiles in databases could lead to discrimination, so the proper degree of protection of the databases is essential.

There are two types of forensic DNA databases: the convicted offender database and the crime scene database. The convicted offender database is a log of STR (short tandem repeat) profiles. STR profiles utilize variability in the number of repeats at a given locus to differentiate among individuals. There are three major forensic DNA databases of individuals convicted of a crime: CODIS (Combined DNA Indexing System), which is maintained by the United States Federal Bureau of Investigation ; the ENFSI (European Network of Forensic Science Institutes ) DNA database; and the ISSOL (Interpol Standard Set of Loci) database maintained by Interpol. The type of offenses for which DNA is stored differs among countries and states. Initially, these databases contained only samples from violent offenders, those convicted of aggravated assault, rape, or murder . However, the value of obtaining DNA from offenders of less severe crimes has been recognized, as many small time criminals become repeat offenders and also more violent offenders. The power of a large bank of DNA samples extends to the possibility of it acting as a deterrent. A match of DNA evidence from a crime scene (which would then be logged in the crime scene database) to one in the convicted offender database rapidly solves the crime, saving time, effort, and money. Conversely, the use of DNA evidence can immediately prove a suspect's innocence.

There are groups of people fervently opposed to DNA profiling for ethical and social reasons. Now that the complete human genome is sequenced, population genetics and other studies are ongoing that have linked genes to phenotypes, predisposition to disease, and predicted response to drug therapy. Should research establish a link between a particular genotype specific to offenders or violent criminals, this could potentially be used to profile potential criminals. In a world where one is guilty until proven innocent, what is the consequence of possessing a genetic profile suggesting that you may one day commit a crime? In society, this individual could potentially be convicted of a crime that he has never even committed. Thus, the opponents of DNA profiling argue, the use of databases to profile individuals for behavior types such as sex offender or violent criminal could affect human rights and civil liberties.

The potential for the criminal justice system to become more genetics-based is another concern. STR loci are based on non-coding sections of the human genome. There are several reasons for this; these regions of the genome tend to be highly variable and thus differ considerably among individuals. The result is a near impossible probability that when all STR loci are taken into account that the profile could belong to more that one human being. Secondly, by using non-coding regions, the STR profiles are not linked to any phenotype or human trait. However, if the genotype of other loci are utilized for analysis additional to STR database uses, it is possible that genetic-based profiling could occur.

Civil rights advocates are concerned that the DNA databases could one day be extended beyond that of criminal offenders to the point where genetic analysis or profiling could be used in a discriminatory manner. It is their intent to protect what exists currently in databases to ensure the DNA is not exploited in any manner that is unethical or violates human rights.

The cause for concern here is the fact that although STR profiles only are logged into the DNA database, be it CODIS, ENFSI, or ISSOL, if the sample is stored, it does include all other genetic information on that individual. Additionally, data obtained from a crime scene that would be entered into the crime scene database could first be utilized to provide a profile of the assailant. For example, DNA evidence left at the scene of a crime may not match any suspect in the criminal database. However, this DNA could potentially be used to obtain the person's sex, height, hair, and eye color and other such traits that may allow the police to generate a physical profile of the perpetrator. Thus, anyone matching this profile could become a potential suspect.

Further analysis of the STR profile via a DNA sample provided by a person under suspicion would easily rule that individual out if he was indeed innocent. However, this too, generates questions of human rights, as although the person is shown to be innocent, any negative consequences or publicity surrounding the investigation could be shown to violate that individual's human rights. Proponents of using genetics to generate a profile of the felon argue that constitutional rights are not violated as no particular group is singled out in such a profile. Furthermore, using such a method could actually decrease racial profiling, as disproportionate finger pointing toward a particular group would be avoided.

Legal implications are constantly considered in courts of law to assure adherence to the respective governing guidelines. In October 2004, President Bush signed into law the Justice for All Act. This law, part of the Advancing Justice Through DNA Technology Act of 2003, provides additional support for victims' rights, ensuring funding for victim's assistance programs. It also extends the DNA databases by providing funds to analyze samples in backlog and sets guidelines for the use of DNA testing post conviction for those who maintain their innocence. The Innocence Protection Act is part of the Advancing Justice Through DNA Technology Act of 2003 (HR 3214/S 1700), and is a United States Government initiative to utilize DNA and forensic evidence to prove the innocence of those wrongly convicted of a crime. It allows convicted individuals access to DNA evidence in order to demonstrate their innocence. Numerous people convicted of crimes, including some on death row, have been exonerated based on DNA evidence that either wasn't available or did not exist as an admissible courtroom technology at their time of conviction.

In Europe, Article 8 of the European Convention of Human Rights defines guidelines for the protection of individual rights. The use of forensic DNA databases has come into question under this law, but the proper use of DNA databases was shown not to be in violation. As the value of using forensic DNA databases across borders is realized, especially across Europe, human rights discussions become even more complex. Although most all European countries are governed by the European Convention of Human Rights, each individual country has its own additional guidelines and regulations when it comes to privacy rights, confidentiality of genetic information, and crime scene investigation . In order to address these concerns on a European basis, several councils and agencies are devoted to these tasks; examples include the Council of Europe convention for the protection of human rights with regard to the application of biomedicine, the United Nations outline for an International Declaration on genetic data, and the European Data Protection Commission.

The diversity of countries across Europe requires consideration of many social and ethical topics regarding forensic DNA databases. Some European Union member countries do not currently have a DNA database in existence. Different opinions exist across Europe concerning which crimes warrant taking a DNA sample. In addition, some countries require consent first, while others do not; and the length of time samples may remain in the DNA databank may be different from country to country. The Interpol DNA Monitoring Expert Group is committed to the development of a consolidated forensic DNA database across Europe as well as internationally. Part of this initiative includes promoting awareness of social, privacy, and ethical issues .

Clearly, social and ethical issues regarding DNA evidence will continue to be a topic of debate. Through education, legislation, and proper use of DNA forensic technologies and databases, the use of DNA evidence will continue to convict the appropriate offender and demonstrate the innocence of others.

see also CODIS: Combined DNA Index System; DNA; DNA profiling; European Network of Forensic Science Institutes; Privacy, legal and ethical issues; Standardization of regulations; STR (short tandem repeat) analysis.

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"DNA Evidence, Social Issues." World of Forensic Science. . Encyclopedia.com. 29 Jun. 2017 <http://www.encyclopedia.com>.

"DNA Evidence, Social Issues." World of Forensic Science. . Encyclopedia.com. (June 29, 2017). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/dna-evidence-social-issues

"DNA Evidence, Social Issues." World of Forensic Science. . Retrieved June 29, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/dna-evidence-social-issues