Police in the German city of Dresden are hunting for a rapist, and they're ready to collect DNA from up to 100,000 men to catch him. German police netted a killer in Cloppenburg in 1998 after 18,000 men were tested, but the Dresden effort could become the largest DNA dragnet ever performed in a criminal investigation.
Dresden police devised the plan after finding identical genetic blueprints from sperm in two rape cases since last September. More than 3000 men so far have submitted to saliva swabs. Participation is voluntary, but the police acknowledge that those who refuse will be scrutinized, according to German media reports.
"I think the strategy is worth it," says Michael Brand, director of the Biotechnology Center at the Technical University in Dresden, even at its maximum cost of $3.5 million. The Dresden police have said publicly that after testing for a match, they will discard DNA from all men who do not have a serious criminal record, as the law requires.
But "even if privacy is protected, to ask for DNA under threat of special scrutiny for those who do not cooperate may be coercive," says Peter Lipton, a philosopher at the University of Cambridge, U.K. "Is this justified?"
