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Justice at last

Created date

December 31st, 2008

The day was Friday, November 16, 1973. A gallon of gas cost 42 cents, President Richard Nixon had just approved construction on the Alaskan pipeline, and 17-year-old Donna Dustin had only hours to live.

After a night out with a friend, Dustin went to a regular party spot in her hometown of Bowie, Md. The next morning two hunters discovered her body in a wooded area just off the Patuxent River.

DNA s role in new leads

Thirty-five years later, cold case investigator David Cordle is turning up new leads in Dustin s murder through the use of DNA. Cordle, who serves as chief investigator for the Anne Arundel County State s Attorney s office in Maryland, looks at the case as a 1,000-piece puzzle.

Right now we ve got about 750 pieces in the investigation, he says. We ve done a substantial amount of DNA work in this case, and we re very fortunate that we have this kind of technology because we re able to do things that, years ago, we wouldn t have dreamed of.

This development in investigative technology started in the mid-1980s and, over the years, evolved into a powerful crime fighting tool that uses the genetic information found in bodily fluids like blood, saliva, and semen as a unique biological fingerprint. It s so accurate, in fact, that a solid match with a specific person carries a degree of scientific certainty in the range of one in 300 billion, meaning that there is a one in 300 billion chance of another individual having the same DNA profile.

Evidence from miniscule samples

According to Angela Williamson, director of forensic casework at the Lorton, Va., based Bode Technology, this is a big leap from the early days of DNA analysis when much larger samples provided odds of only one in four. '

DNA testing wasn t very discerning or distinct when it first came into use, Williamson says. It was around the mid-1990s that the technology for collecting and processing DNA improved, and that s when you could use a smaller amount of DNA to get more information about a person.

Crime scene investigators can recover DNA evidence from a small drop of blood on the floor, the bodily fluids exchanged during a sexual assault, or skin cells underneath the fingernails of victims who scratched their attackers. Even the surfaces of objects and clothing can hold skin cells that a person sheds simply by making contact with them.

Sometimes called touch DNA samples, investigators might pull this material from a hand smudge on a window or lift it from the fibers of someone s sweater using a razor blade or a piece of tape. According to Williamson, this type of DNA evidence accounts for about 30% of Bode s lab work, which comprises roughly 4,000 cases a year from state law enforcement, special agencies, and attorneys around the country.

Indeed, cold case units that rely heavily on DNA are springing up throughout the U.S., some of them as leaders in the field. For instance, the Denver, Colo., police department and district attorney s office are reviewing nearly 1,000 unsolved homicide and sexual assault cases that have useable biological evidence through their Denver DNA Cold Case Project.

The Project utilizes a state- and national-level DNA databank that constantly searches for matches between the DNA profiles of convicted felons and samples related to unsolved cases. Of the 500 investigations worked so far, the database has returned more than 100 hits indicating possible suspects.

Case in point

An example of the Project in action involves a case from the mid-1990s, in which a man raped a blind and hearing-impaired woman in her apartment. Because of her disabilities, it was virtually impossible for her to identify her attacker, says District Attorney Mitch Morrissey, who co-founded the Cold Case Project with a Denver homicide lieutenant.

The case went unsolved for several years until this man broke his son s arm in a child abuse situation, Morrissey adds. He was sent to prison for this crime and, as a result, ended up in our DNA database.

When his information was loaded into the system, the databank registered a match and alerted Morrissey, who used the evidence to prosecute and convict the woman s attacker in 2004 nearly ten years after the crime.

For me, it was one of those moments where everything fell into place, he recalls. Here s a victim who couldn t see or hear her attacker, and we were there in court getting her justice. The DNA answered the question of who committed this crime and provided justice for a woman who wasn t able to do that for herself.

David Cordle is confident that DNA will do the same for Donna Dustin and her family. Since the start of our investigation in 1997, we ve gone through five different generations of DNA testing where we retest samples using improved technology, he says. Because of that, we have the ability to solve this case.