Police showed up at Ashley Berden's home at 4 a.m. and demanded she take a Breathalyzer test. She faced a $100 fine if she didn't. The 18-year-old had left her purse at a party that police had busted for underage drinking, and that was sufficient for the Thomas Township, Michigan, police to demand a test. Under state law they didn't need a warrant to demand the test of someone under 21. And township police reportedly routinely raid parties and demand to test everyone under 21. The test on Berden showed she hadn't been drinking. Now, she and three others are suing the state, local police and sheriff's departments and the Central Michigan University Police Department, seeking to have the law permitting warrantless tests of those under 21 struck down.