For many years, prosecutors have relied on both physical evidence and eyewitness testimony to pursue their cases against accused criminals. Since the US Constitution guarantees that the accused is “innocent until proven guilty,” prosecutors must create a compelling chain of evidence to persuade jurors to convict defendants, especially those accused of violent crimes. However, as technology advances, a growing number of those incarcerated being incarcerated are being exonerated.
Numerous advances in technology and psychology have enabled prosecutors, defense attorneys, judges and jurors to gain a clearer picture into the crime scene. These advances are also becoming important resources for criminology colleges who are looking to train the legal professionals of the future. These new techniques have allowed those wrongfully accused to be exonerated, and those mistakenly imprisoned to be set free.
The biggest source of forensic evidence that both reduces and overturns wrongful convictions is DNA evidence. Thousands of previous convictions have been overturned on the basis of DNA evidence. Further advances in DNA testing technology have reduced the time to return test results from as much as eight weeks to as little as forty-eight hours. As the understanding of the human genome grows each year, forensic scientists will also be able to detect specific genetic markers which can eliminate potential suspects and reduce the probability of a wrongful conviction.
One of the most notable overturned convictions came in the case of the beating and rape of a woman in 1989. Three young men were tried and convicted in the famous “Central Park Jogger” case. In 2002, a judge overturned the convictions of Kevin Richardson, Raymond Santana Jr. and Antron McCray after DNA evidence cleared them of the crime. The DNA evidence also pointed to the true attacker, Matias Reyes, who was later convicted in the attack.
Forensic Science Standards
According to the Innocence Project, a non-profit group that deals with the issue of wrongful convictions, about half of the convictions later overturned due to DNA evidence were the product improper forensic evidence procedures. Some of the previous forensic procedures, such as hair analysis, bite mark matching and ballistics testing, have not undergone the scientific rigor of DNA testing.
In order to standardize forensic practices, several states, including Texas, New York and Virginia, have developed forensic science commissions. These commissions also investigate cases where local forensic investigators have either mistakenly or maliciously manipulated potentially exculpatory evidence. The National Academy of Science has also recommended the formation of a similar committee to codify forensic evidence procedures on a federal level.
Wrongful Conviction Statistics
The Innocence Project has also compiled a series of statistics on wrongful convictions:
• Since 2000, 222 convictions have been overturned by DNA evidence.
• Of the 289 defendants exonerated by DNA evidence, 180 were African-Americans
• The most exonerations occurred in Texas (44), followed by Illinois (41) and New York (27).
Advances in technology in the criminology field, combined with higher public awareness, have shown that the potential for wrongful convictions appears to be on the decline. As the science of genetic testing continues to grow, the legal system must catch up to insure that innocent defendants remain free and that the true perpetrators are brought to justice.