Why would you comply with a request to keep criminals on your website? I'm sure it made the police's job easier, but I would never comply with something like that for my own, and for my users sake.
If you kick them off before they do criminal behaviour then the police can't do anything and you'll just wait to see them back with a new VPN/identity.
To be clear, we didn't leave individual predators on the site. We did whatever we could to remove them and helped the police catch them if there was enough evidence.
It's the reputation we let stand.
Doesn't a reputation of allowing criminals bring in more criminals, putting your users at risk?
That is what I said a few posts up. It's a policy I felt uncomfortable with even then. I just wanted to clear up that we didn't leave individual bad actors on the site to my knowledge.