maryland vs king

[Danzig]

http://news.yahoo.com/court-police-d...ccmt-container


scotus ruled 5-4 that states and the fed can collect dna at arrest, not conviction, and overturns a lower court ruling in maryland.


i've read this article, and went to scotus blog, but i need to read more. but at present, i have to say i'm not happy with the ruling at all.
and as a yahoo commenter said, if you're arrested, but not convicted-what happens to your dna? is it retained, and for how long? what about search and seizure and probable cause for searches?