The laws in CT have changed over the last few years making it very hard to own a wild animal in your place of residence. I'm not sure how old it was, but I know she owned the chimp long enough to where she got him before the tighter laws were implemented. Basically she was allowed to keep it because He was grandfathered in to the previous rules.
That being said, I know its still a wild animal but it wasn't AS wild as say a tiger or lion in my opinion. The chimp could dress itself, ate human food at the the dinner table with a fork and knife, slept in bed in pajamas, knew how to use keys to unlock doors and open them, etc.
I'm not sure of the exact medication, but she gave him something like a zanex a little before the attack. Dr's now think that may have been the cause stating that human medications can react differently in certain animals.