Family Ties

Ever wondered why you look like your parents? Or maybe why you have the same personality as your aunt, or the same balding pattern as your grandfather? Well, some of it is nature and some of it is nurture. We are not about to get into that, but we are about to learn just how much alike we are as far as breaking the law.

It’s called kinship analysis, or familial searching: Comparing the DNA fingerprint of crime-scene samples to the relatives of known criminals. That doesn’t make much sense at first, but let me explain. CODIS is a national database consisting of DNA profiles of convicted felons and samples from unsolved cases. So when a crime is committed and the police do not have a suspect, any DNA from that crime-scene gets compared to this national database to see if, by chance, the person who committed this crime happens to have his or her DNA profile already on record. The match must be exact, throughout the entire profile. If it is, it’s called a ‘cold hit.’ In kinship analysis, however, the match does not have to be exact, only similar. This strategy is based on two central facts: According to research studies, close relatives of known criminals are more likely than others to break the law, and because these two individuals are related, their DNA fingerprints will be similar. So, that suggests that if a DNA specimen, found at a crime scene, has a profile that is close to, but not exactly the same as, that of a known criminal, then a close relative may be the culprit.

This is not illegal in the United States, but it is rarely acknowledged and utilized by state law enforcement. In Britain, where DNA laws are more relaxed, the approach has been the turning point in several cases, and proven itself a vital element in crime-fighting. For example, in 1998, a DNA specimen was obtained from a murder scene, but with no suspect, the police had nothing to compare the profile with. However, they were able to use the murder-scene profile to search for familial matches. They found that the profile was similar, but not exact, to that of a 14 year old boy’s, whose DNA was on file with the police. Investigators obtained samples from the boy’s uncle, and found a perfect match. He was convicted and the case was solved.

A 1999 Justice Department survey found that 46 percent of prison inmates had at least one sibling, parent, or child who had been incarcerated at some point. And, computer models forecast that ‘cold hits’ (perfect matches) might increase by 40 percent if they were to check the DNA patterns of criminals’ family members when searches generate near misses.

Civil libertarians say “It’s an infringement on our rights. If I give up a DNA sample, does that mean I’ve also committed all my blood relatives to a search?” That is an important and valid question. That’s where the lawmakers must look closely at the possibilities of this new technology, and American citizens must decide if they are willing to be included in DNA searches, or if they are ready to take their chances with more criminals, at large and on the street.