DNA Databases and Privacy

In a relatively new and questionable law enforcement procedure, individuals arrested for a crime but not convicted can be subject to the taking and retainment of their DNA, which is then filed in a DNA Criminal Database, regardless of the status or guilt.

"America's Most Wanted" host John Walsh enthusiastically supported the expansion of the DNA Database, "We now have 18 states who are taking DNA upon arrest. England has done it for years. It's no different than fingerprinting or a booking photo."

Many in the human rights community disagree. The European Court of Human Rights unanimously ruled in 2008 that the UK's policy of keeping the genetic material after the arrestees' release violates their rights to privacy and family life. The UK at the time had stored 4.5 million DNA profiles - more than 5% of the total population of the country - and 1/5 of the DNA information was taken from people with no criminal record.

Advocates of the database expansion argue that including innocent people's DNA protects communities - the idea being that the more information they have the more likely a sample left at a crime scene might find a match that leads to an arrest.

But DNA forensics is an art and science involving complex statistical calculations and careful handling of evidence. The larger the database searched find a high degree of certain, the more complex the results of that search can be.

DNA matching is based on the idea that no two people can share the same genetic profile. But in a 2005 examination of Arizona's criminal database of 65,000-plus entries - more than 100 profiles were similar enough for many experts to consider them a "match."