I'm not sure, but I think the phrase "an open and shut case" probably applies to this situation (via CT News Junkie):
Ken Krayeske, a freelance journalist, photographer, and law student who was arrested while taking photographs during Gov. M. Jodi Rell’s inaugural parade in January, filed a federal civil rights lawsuit Thursday against the City of Hartford and its police officers involved in his “false arrest.”(There's more at CT News Junkie)
Krayeske made a state police hit list for his political activities, including his role as campaign manager for Green Party candidate Cliff Thornton who ran against Rell in the Nov. 2006 election.
The federal lawsuit claims that prior to the inaugural parade a member of the Connecticut State Police informed Hartford Police that Krayeske “was among a group of political activists who posed a possible threat to the governor.” But the state dropped the charges in March when it discovered there wasn’t enough probable cause to prosecute Krayeske.