Moose

Corrected entry: At the end of the film, Dumbledore announces to the school that Cedric Diggory was murdered by Voldemort. He wasn't, he was murdered by Wormtail, and Harry (who presumably gave them that information) knew that.

Moose

Correction: But since Voldemort ordered the killing of Cedric (and most likely would have killed Wormtail had he refused), he is ultimately responsible for Cedric's death. Besides, the workings of a group, such as the Death Eaters or the Nazis during WW2, are often attributed to its leader, even if they do not contribute actively themselves.

Twotall