When
scientists James Watson and Francis Crick
first mapped the structure of the DNA double
helix a half century ago, little did they
know that they were also unleashing a powerful
weapon in the fight against crime and terrorism.
How
powerful? Extremely. Today, DNA evidence
and tests can:
...Establish
both guilt and innocence;
...Link together seemingly unrelated cases
(including serial crimes) so they can be investigated
in tandem;
...Act as a set of "genetic fingerprints"
that can positively identify not only criminals
and terrorists, but also the remains of victims
and missing persons, often years later;
...Keep dangerous felons behind bars by connecting
them to other offenses;
...Quickly eliminate suspects and speed up
investigations; and
...Bring closure and peace of mind to victims
and their families by solving otherwise unsolvable
crimes.
So
how can DNA do all this?
DNA can uniquely identify an individual in
ways that even fingerprints can't. DNA is
found in virtually every human cell. It can
be extracted from hair, teeth, bones, and
body fluids (blood, saliva, semen, even sweat!).
It leaves traces on everything from cigarette
butts to postage stamps, from shirt collars
to napkins. And it lasts for years -- even
in harsh conditions, even when there's little
left of human remains. For example, following
the 9/11/01 attacks, investigators were able
to find traces of DNA in the rubble of the
World Trade Center that identified victims
and brought some measure of closure and relief
to their devastated families.
But
the crime-fighting power of DNA really didn't
begin to be unlocked until 1990.
That's when the FBI began a pilot project
called the Combined DNA Index System,
or CODIS -- which, following
Congressional approval and funding, became
fully operational in 1998.
What's
CODIS? CODIS is a three-hitter: computer
technology (a database program and software),
forensic science (DNA profiles rigorously
measured and maintained), and telecommunications
(the ability of local, state, and federal
labs to share information and communicate
electronically) all rolled into one.
Simply
put, CODIS stores DNA profiles from around
the country in a series of local,
state, and national databases, all linked
via computers, enabling crime labs at every
level to share and compare DNA profiles electronically.
Lightning fast searches using CODIS can link
DNA found at one crime to other crime scenes
and to convicted criminals whose DNA is already
on file.
Tomorrow,
we'll share more specifics on how CODIS works,
talk about how it just passed a significant
milestone, and pass on a few recent success
stories. Stay tuned!
