submit by troym; comments by blogger jgl
Articles like this have been all over the news for a couple weeks now. NPR did a fine story on it here. Troy sent in this article and made the point "using DNA profiles of a suspects' family members in criminal investigations (is this not a civil liberties issue)?" It is.
|Victims of mass tragedies such as Hurricane Katrina and the World Trade Center attacks are often identified using the DNA of surviving relatives. Now, scientists say the same technique could help nab criminals.|
When crime scene evidence does not match anyone in the criminal DNA database, investigators could also check for close matches. These near misses could be close relatives of the suspect, said forensic mathematician Charles Brenner of DNA-VIEW in Oakland, a visiting scholar at UC Berkeley.
A relative's match would not provide any direct evidence for building a case against a suspect, but it might provide new leads.
"It could be beneficial," said Sgt. Brian Dickerson of the Richmond Police Department's family services unit. "Anything that gives us additional leads would be good."
"There's obviously a balancing act between privacy and public safety," said John Tonkyn at the state DNA lab in Richmond.
Here is how it works. DNA found at a crime scene does not match any criminals in the database. However, it might "closely match" 5 criminals in the database. So in theory, the guilty person could be a brother/son/relative of any one of the 5 criminals.
The technique can definitely be beneficial for investigators, but essentially it creates a somewhat random pool of "potential offenders", all but one of whom is innocent (or all of whom are innocent). So the downside is that the police have an "excuse" to bother a bunch of people that had nothing to do with the crime. In theory, the police would never abuse this power, but a similar thing happened to Brandon Mayfield when his fingerprint almost matched that of the Madrid train bomber.
For the DNA analysts out there... i first heard about this being used with CODIS STRs. In the article, the focus is on using Y-STRs. it seems like this would be worse (create a larger pool and requires extra testing). thoughts?