But then, he didn't know how much the police already knew about him.

The police could not know what she was doing up here tonight.

I'll tell you everything, but the police don't know until I say so.

Well, the police always did know how to look after themselves.

If the police knew he was around here, why didn't they do more to stop him?

The police did not know when the girl was last seen in school.

But the police do not know where he spent the rest of his time.

Not until we find out if the police knew anything about either of them back then.

The police did not know how much money was taken.

How can the police still not know anything about him after nearly two weeks?