Paul Brown was working on his computer in his north suburban home when police smashed in the front door, pointed guns at and handcuffed him and other family members, and ransacked the house in a search for drugs. The authorities had burst in immediately after a postal worker delivered a package to the home that they said contained marijuana. But a search of the house found no further contraband, and officers left without making an arrest. Brown, outraged, said he was sure the cops had the wrong house. Police maintained they had the right place, but the target of their...