In a major expansion of the US government's DNA collection practices, officials plan to collect DNA samples of every citizen arrested by a federal law enforcement agency and all immigrants detained by a federal authority. The move will add 1.2 million people's genetic blueprints to the federal database every year.

Until now, federal authorities have only taken DNA samples of those convicted of a federal felony. The new rules would mark the first time the feds have collected DNA from those who are arrested but never charged and from people other than US citizens and legal permanent residents.

The proposed rule - which is subject to a 30-day public comment period after being published in the Federal Register - is a major expansion to the once-narrow confines of DNA collection. The National DNA Index System (NDIS) was established in 1994, to store profiles of people convicted of rape, murder and other serious violent crimes. A decade later, feds began indexing records of people convicted of any felony. Around the same time states that also collect DNA samples of people arrested (there are 13 of them now) began sharing that information over to the NDIS.

Civil libertarians are none too happy about the move. They complain of mission creep and say it's an invasion of privacy of people who are arrested but who are never charged with a crime, or who are later acquitted. Those backing the new rules say federal employees may not use the records to identify genealogy, genetic traits or diseases. They also say people wrongly arrested can petition the Justice Department to destroy the records.

But according to the Associated Press, it can take up to two years to get records expunged, and in the meantime, it's unclear what is to prevent employees from skirting those rules. Only last month the US State Department admitted that workers had snooped on the supposedly private passport records of all three presidential candidates.

Federal authorities arrest about 140,000 individuals every year. About one million more individuals are detained for being in the US illegally. The NDIS is about to get a lot bigger. ®