"well - I know I've been a bit of an idiot - "
-Ludo Bagman, giving testimony (GF 30)
At his trial, Bagman admits having passed information to Augustus Rookwood, but claims that he didn’t realize that Rookwood was working for Voldemort. Mad-Eye Moody, for one, has no trouble believing Bagman had been foolish rather than deliberately treacherous. Barty Crouch, Sr. thinks that Bagman should be sent to Azkaban, but the jurors unanimously vote that he should go free. (GF30)
Like Karkaroff's trial, this one was almost certainly within a year or so of Voldemort's downfall, as Barty Crouch was presiding (GF30).
Keep in mind that this is the second of three sentencings Harry watches in succession through the pensieve. All three of these memories are from Dumbledore, himself, and focus on the effort to identify and convict supporters of Voldemort in the wake of his downfall. -BB
Just about everyone in the courtroom seems to be biased in favor of the handsome, charming Quidditch star. It certainly doesn't seem like there is any reason to think that Bagman was in league with Voldemort, but the fairness of the trial could be seen as questionable. -BB