Clearly Google already has a process to escalate detection to the police so banning the account based on what happens there doesn’t seem like a big leap.
The police aren't going to recommend a ban. They don't want people banned. They want people arrested, tried, and convicted for criminal possession. They're going to recommend keeping the account open until they have enough evidence to take it to court.
Google probably doesn't share the same rosy outlook. Long-running investigations that do not result in charges will be bad PR. The headline "Google shared private data on 100s of innocent users with law enforcement" will not be received well.