Links of the Day: 2008.02.24


Familial Searching: Making CSI a Family Affair

The Wall Street Journal is reporting a new forensic technique in Great Britain – familial DNA searching. Supported by a DNA database, to which anyone arrested must contribute, the bobbies run a sample (of blood, semen, hair, etc.) left behind by their wanted criminal. If they don’t find a match, they look at the close, possibly related matches, and try to find the criminal by interviewing his or her possible relative.

The article includes the predictable points…

  • “DNA is the best kind of forensic evidence there is — it’s better than an eyewitness account.”
  • “The Home Office, which oversees the police forces of England and Wales and their combined DNA database, say those who are innocent have nothing to fear from providing a sample. They say retaining this evidence is no different from recording other forms of information such as photographs and witness statements.”

… and counterpoints:

  • “Unlike old-fashioned fingerprints, [civil liberties groups] say, DNA contains health and hereditary data such as paternity markers that could be misused.”
  • “[Civil liberties groups] say a DNA-based “ethnic inference” test can provide uncertain predictions about the race of potential suspects that may mislead the police or reinforce existing prejudices.”

It seems that few people object to retaining DNA profiles of convicted criminals. It’s the involvement of innocent people — both the ones who were arrested but let go or acquitted, as well as the relatives of the perpetrator-in-question who are likely not involved with his or her crime.

Familial searching doesn’t present a change in basic police procedure. The police are always going to question relatives of a suspect.

On the other hand, they usually know who their suspect is first.

Collecting DNA is not terribly different from collecting fingerprints or retinal patterns.

On the other hand, you can’t (as far as I know) determine a biological relationship between people based on fingerprints or retinal scans.

For better or for worse, this is going to happen. People (in the United States, at least) are going to be furious about it, but someday, eventually, we are all going to have a DNA sample attached to our entry in the national ID database. It’s just a matter of time. Instead of fighting it wholesale, we need to be sure that the we properly bring the definition of “probable cause” and “unreasonable search and seizure” into the 21st century.

The Gene Police [WSJ]