The Bush Administration is pushing to change federal law to allow permanent retention of DNA samples from those arrested but not necessarily convicted of crimes.

Adding profiles from thousands of adult arrestees and juvenile offenders would greatly expand the DNA system's worth by increasing the number of potential matches, administration officials say. Justice Department officials have discussed potential changes in federal DNA law with key members of Congress and are pushing for legislation this year.

The American Civil Liberties Union (ACLU) is objecting to this proposal. The arguments here are interesting because this is not just an issue of being able to match a person's DNA with DNA that is found to be in some way connected with the commission of a crime. Another issue is that eventually many characteristics of a person will be discovered from analysis of a DNA sample. If genetic variations that cause particular personality types are discovered then a person's DNA could be analysed to see if it has genetic variations that are linked to particular personality and behavioral characteristics.

Governments have many conceivable uses of information about genetically determined characteristics. For instance, if there are genetic variations linked to how well someone can perform as a particular type of soldier then the military might want to look at the DNA profiles of all juvenile offenders (whether they were arrested for drunk driving or assault or just running away from home) to identify promising recruits for special forces. Also, if there are genetic variations that are more or less associated with loyalty and betrayal then intelligence agencies might want to look for recruits who are least likely to betray their country.

Some youthful offenders never commit another crime and some future career criminals are first caught committing a crime that is not particularly serious. Yet if there are genetic variations that make a person more prone to commit crime then someone identified from a first arrest (even if the charges are dropped) as having a DNA profile that matches a career criminal could then be pegged for future surveillance. Prosecutors could conceivably even push for long prison terms for first offenders if their DNA profile matches that of repeat offenders.

Widespread collection of DNA samples can potentially speed the rate of advance of understanding of the human genome. If it becomes legal to do so then as the cost of DNA sequencing falls the DNA samples collected from criminal suspects could be compared on a massive scale in order to discover which genetic variations correlate with which types of behavior. This would greatly help in the identification of genetic variations that contribute to intelligence, personality, and other human characteristics. If basic biometric data is collected (height, eye and hair color, weight, and assorted other measurable characteristics) then additional links between genetics and phenotypic characteristics could be discovered more easily.

The battle over DNA sample collection is just the first round. There will be many more rounds of political battle over what analyses should be allowed to be done to DNA samples in government hands. But the biggest question of all will be over what will be the allowable governmental uses for each DNA analysis.

Governments will not be the only users of DNA analysis results. Insurance companies and other businesses of course could find many applications for such data. However, personal uses of DNA analyses promise to be interesting as well and probably unstoppable.

Update: The British government has also just proposed legislation to greatly increase the collection of DNA samples of people not convicted of crimes.

Police will get powers to obtain and retain the fingerprints and DNA profiles of innocent individuals under proposed laws announced yesterday. A privacy expert with law firm Masons says this means that DNA profiles from nearly half the male population will eventually be contained in the police DNA database – and unless a pending House of Lords decision overrules lower courts, this practice will not breach human rights legislation.

The article on the British proposal brings up an interesting issue: criminals could get DNA samples from innocent people and then deposit such samples at the scenes of crime. This will become easier to do with time as equipment for growing human cells in culture becomes more widely available, cheaper, and easier to operate.