By Elizabeth Wong, Associate Director
When I first heard about the resolution of the “Grim Sleeper” case in California, I thought it was something straight out of a CSI episode.  Using a technology known as “familial DNA,” scientists were able to identify a relative of an unknown serial killer in Los Angeles said to be responsible for at least ten murders. Narrowing the pool of suspects to members of a single family, the police were able to nab the killer.
The case had frustrated police for more than 20 years.  They had a description of the killer and his DNA, but they didn’t know his name or where he lived.  Last year they even announced that the case had probably reached a dead end.
Things changed, however, when Christopher Franklin was convicted of a felony weapons charge and his DNA was entered into the state’s DNA databank.
Using familial DNA research techniques, the California DNA lab concluded that the “Grim Sleeper” was not Christopher Franklin but a close relative of his.  Based on age, crime dates, and other factors, the police focused their attention on Christopher Franklin’s father,  Lonnie David Franklin, Jr.  After following the senior Franklin, they were able to obtain a sample of his DNA from pizza he had partially eaten and thrown away.  The sample proved to be an exact match with the Grim Sleeper’s.
Lonnie Franklin’s arrest is surely a welcome outcome for the families of the Grim Sleeper’s victims and a relief to the residents of Los Angeles.
And, at first blush it appears to be a welcome technological advance in crime solving that could quickly spread beyond California and Colorado, the only two states that regularly use it.
But like most new technologies, there is downside to familial DNA testing that needs to be fully explored before we blindly embrace its everyday use.
You may be asking, what exactly is a familial DNA search?  Like fingerprints, DNA samples are unique to each person.  But unlike fingerprints, where relatives do not share similar patterns, DNA from relatives is similar.  The closer the relationship, the more similar the DNA.
So, in addition to searching DNA data banks for exact matches with DNA found at crime scenes, scientists can now search for partial matches and thereby identify known criminals as relatives of someone who may have committed a crime but whose DNA is not in the data bank.
This is not a magic elixir that is going to solve a lot of crimes.  First, a criminal suspect can only be identified by this method if he has a relative who has been arrested and had his DNA taken.  Second, the matching process isn’t always perfect.  There are lots of people who are not related but may have similar enough DNA to be viewed as relatives. It all depends on what degree of matching the police are using.  Third, the partial match, even when it works, identifies lots of relatives, so the police may still have their work cut out for them.  Fourth, it is not cheap.  The “Grim Reaper” investigators reported that the DNA search itself cost $40,000.
Moreover -- and of greatest concern to us -- is that it introduces something like scientifically verifiable guilt by association into the investigative process.  How many individuals are now going to be identified as suspects solely because they are related to someone who may have committed a crime?   As true as it is that we are all innocent until proven guilty, that doesn’t mean we can’t be put through hell until the police, the prosecutor and a jury decide one way or the other.
The way we balance individual liberties and law enforcement is by placing restrictions on the police.  They can’t arrest you without probable cause that you have committed a crime.  Except for emergencies, the police can’t search your home without a warrant.  The government can’t listen in on your private conversations without court approval.
DNA is a valuable tool that has proven its worth.  It not only helps to convict those who break our laws, but it has been used to demonstrate the innocence of numerous individuals who were convicted of a crime in a court of law.
But there can be too much of a good thing.  The primary function of DNA until now has been to narrow the field of suspects in a particular case, excluding everyone except the person implicated by a DNA sample.  Familial DNA testing stands that function on its head by enlarging the field of suspects to include anyone in the family (and beyond in some cases).  Any technique that expands police power should be met with at least some skepticism and approached cautiously.  It is important that we make sure we’re using familial DNA searches properly so that it does not give police reason to cast too wide a net when looking for suspects.
I don’t claim to be an expert on DNA, but before we start using familial DNA searches in Virginia on anything other than a very rare occasion, I want us to thoroughly study its impact on civil liberties and to make sure it is used in a way that both helps to solve crimes and protects civil liberties.