I don't blame the chimp as he was acting like chimps do.
The owner, however, definitely deserves the finger pointed at her. He was ill with Lyme disease. I know that in humans, Lyme mimics many MS symptoms. If that chimp felt anywhere near as bad as I do most days, he should have been secluded in a cage or vet's office while getting treatment. She knew he had been agitated, and she has now admitted to giving the chimp Xanax in his tea that morning (she says 5-10 minutes before the attack, but yesterday she said she had "never ever" given him Xanax). Xanax can cause aggressiveness in humans, and it had never been prescribed to the chimp.
As for the police shooting him, I don't blame them at all. And no, I don't think sedatives were the answer. The owner had stabbed him with a butcher knife multiple times and hit him with a shovel. It had only enraged him more. She told the police on the 911 call to shoot him. He had ripped off the woman's face and most of both of her hands and he ate them!
If they had come across a person who was doing or had just done the same thing, they would have killed him too.
It seems to me that the owner didn't want an animal, she wanted a child and/or companion. She fed him lobster, taught him to dress himself, he could drink wine from a goblet, he could even drive a car. He was a chimp, not a person. Chimps shouldn't drink wine. Chimps don't wear clothes in the wild. Chimps definitely shouldn't drive.
Wild animals, or exotics, can be kept responsibly. She wasn't respecting the wildness of this animal, nor even the fact that he was still an animal. She treated him like a little person. She was anything but a responsible exotic animal owner.