42 U.S.C. ยง 1983 waives sovereign immunity for the government and allows you to sue the government and its agents for constitutional violations. These are notoriously hard to prove because of cost, bad law, bias in favor of the police, and police lying. Has there ever been a situation where members of a police unit were sued for, say, a raid gone wrong, and convicted because of this law?
Try asking in /r/law.