In the USA, a frame-up (frameup) or setup is the act of framing someone, that is, providing false evidence or false testimony in order to falsely prove someone guilty of a crime.
Sometimes, the person who is framing someone else is the actual perpetrator of the crime. In other cases it is an attempt by law enforcement to get around due process. Motives include getting rid of political dissidents or "correcting" what they see as the court's mistake. Some lawbreakers will try to claim they were framed as a defense strategy.
Frameups in labor disputes sometimes swing public opinion one way or the other. In Massachusetts, during the 1912 Lawrence Textile Strike, police acting on a tip discovered dynamite and blamed it on the union. National media echoed an anti-union message. Later, the police revealed that the dynamite had been wrapped in a magazine addressed to the son of the former mayor. The man had received an unexplained payment from the largest of the employers. Exposed, the plot swung public sympathy to the union.