Leonard's alibi and Romaine's letter
At the trial, doesn't Romaine's letter and assignation, even though the letter talks about implicating a naive Leonard, still lose him his alibi and any proof that he was at home that evening?
It doesn't mean he was at Emily's house either but it's strange that it's that evidence that completely lets him off, when it actually goes against his story of being at home with her.
Only watched it once so might have mis-remembered.