It’s not clear the circumstances that they do record and monitor, but they definitely do monitor sometimes. They’ve reported crimes that happen in the Waymos, like this incident where they reported some teenagers that had an illegal firearm: https://news.ycombinator.com/item?id=49672549

That same story mentions another instance where some kids had alcohol and toy guns. So maybe there is AI that detects firearms? And then a human intervenes? Its not very clear.