its a misdemeanor, and its possible to be held civilly responsible, I said as much initially. I don't think its "no big deal", but while underage she was 20, not 16. everyone keeps saying "he let her" leave, she was an adult and she chose to leave, IF his story is true. it may not be. we don't know.
She was underage and I have posted the link that police confirm he knew she was drinking and was allowed to leave. Why would he like about it? Her keys should have been confiscated and her host had a duty to ensure her safety. She is now missing and is not to blame. She is a victim.