weird ending

So this man suffered a head injury and couldn't remember that he was innocent, yet he knew the child's name when they asked it? It's just strange that he was unable to remember that he had nothing to do with his murder yet he could recall the name. Part of me wonders if he felt there was no use in trying to claim innocence - that the parents wouldn't believe him anyway - so he ended it all by hanging himself at the end and figured maybe he was atoning for the other guy's sins or something. Just a thought. Nothing about the ending was as clear as some have stated.