Identification Errors Increase as DNA Science Expands
By: Gerri L Elder
DNA
evidence is largely regarded as the final word in the identification of
criminal suspects. It is the most reliable forensic science and plays
an integral part in many criminal cases, to the frustration of some criminal defense attorneys. However, as effective as DNA identification is, it's not perfect and has limits.
A recent article by The Los Angeles Times
highlighted the imperfections in DNA science. Contamination of samples
or samples that go untested for many years can produce inaccurate
results and reap havoc on the justice system.
In 2004, Jerry Bellamy was arrested in New Jersey and charged with the murder of Jane Durrua, reported The Los Angeles Times.
Durrua, an eighth-grade student, was raped, beaten and strangled 36
years before Bellamy's arrest. Prosecutor John Kaye announced that
through DNA science, the mystery of Durrua's murder had been solved.
As it turned out, Bellamy did not murder Durrua. Two years after his
arrest, investigators discovered that DNA evidence from the murder
scene had been contaminated. Bellamy's DNA was being tested in an
unrelated case at the same lab that the Durrua crime scene evidence was
being examined. When this error was discovered, Bellamy was freed.
Another man was arrested for the murder, but died before trial.
DNA evidence is often used to exonerate people who have been wrongly convicted;
however, mislabeled and contaminated samples can also link innocent
people to crimes. During criminal trials, DNA evidence is represented
by prosecutors as infallible, and jurors generally believe that DNA
can't be wrong. The problem is that it can - and sometimes it is.
In
some cases, crime labs have huge backlogs of DNA samples that sit
untested. While this evidence collects dust, criminals who could have
been caught have the opportunity to commit another crime.
There
have also been debates about whether DNA collection and storage is
constitutional. Civil rights advocates argue that storing DNA of people
who have been arrested but not convicted is a violation of privacy.
Despite the imperfections, backlogs and questions about violating rights, a dramatic DNA database expansion in planned.
Starting
in January 2009, California Proposition 69, which passed in 2004, will
allow authorities to store the DNA of anyone arrested on suspicion of
serious misdemeanors and felonies. These DNA samples will be stored
regardless of conviction. California's DNA database is expected to grow
by 300,000 in 2009.
The FBI's national DNA database
currently contains approximately 6.4 million profiles. This database is
expected to grow by about 1.3 million each year with the addition of
DNA profiles from federal arrests and illegal immigrants.
When
Prop. 69 passed in California, it was believed that innocent people
should not be afraid of having their DNA profiles stored in a database.
Now that more errors have been discovered, it seems that there may be
reason for concern.
UC Irvine criminology professor William Thompson is considered the leading authority in the U.S. on DNA laboratory error. The Los Angeles Times
obtained documents from five state-run and three county forensic labs
and discovered reports of many laboratory errors or "unexpected"
results over a five-year period ending in 2007. Thompson reviewed the
records for The Times and concluded that laboratory personnel routinely make mistakes that could lead to the false identification of suspects.
Without a doubt, as DNA databases grow, so do the chances that innocent people will be linked to crimes.