Apollo Justice: Ace Attorney Trilogy

Found at the end of the first game, in the fourth episode. At the very end you're given the choice to vote Guilty or Not Guilty.

Voting Guilty leads to the bad ending, but you can simply reload a save to choose the other option. While it doesn't let you save once the scene has changed to the Jury one, you can save in the court at any time prior to that and it should be obvious when it's about the change. Also, for me at least the game made an auto-save at the last possible moment. So, don't worry at all about missing this one.