Wisconsin Governor James E. Doyle, a former attorney general, said taking arrestees' DNA is no different than taking their fingerprints or mug shots.If that is really the case, then presumably Gov. Doyle's own reaction would be the same whether he was getting his photo snapped or having his personal bodily material forcibly scraped away from the inside of his mouth with a plastic tool by the government.
The latter activity appears pretty clearly to be a seizure within the meaning of the Fourth Amendment. And its reasonableness, a constitutional requirement, is certainly not a foregone conclusion.
Furthermore it's not correct to say that "21 States allow DNA to be taken when people are arrested for some crimes." In several of those States DNA may only be collected following a probable cause hearing before the judicial branch, not at booking by law enforcement, which is what some in the Wisconsin legislature are proposing.
One of the very few States that has so far imposed a questionably broad and sweeping regime of DNA collection similar to the one now being contemplated in Wisconsin is California.
For a preview of what can inevitably be expected here if this bill becomes law, please enjoy some thought-provoking edification in the form of a class action complaint (.pdf; 26 pgs.) filed by the American Civil Liberties Union only a few days ago in the Golden State, where "approximately one-third of the hundreds of thousands of persons arrested for felony offenses in any given year are ultimately never convicted of any crime whatsoever."
That is, according to 2007 figures, 101,000 innocent persons would have had their personal biological material forcibly seized from inside their body cavities by a former Austrian weightlifter without a warrant and without a probable cause hearing in front of a judge.
Mindful of this fact alone, I would submit that whatever remains of the Framers' own DNA is rotating centrifugally in their sarcophagi.