Armand is saying that Costigan attacked him first, that he fought back and then Costigan stabbed him in the chest with a knife. I know that much is true from the wound in his chest after I went to save his life. He either doesn't know why the attack happened or he's not telling me, but I believe him this time when he claims to not know. Aside from self-defense, the only reason he even fought back was because he lost control. Armand...has memory issues and we've been trying to work through those. This must have triggered something.