They should have called the FBI, the FBI would have requested a warrant, the Judge would have approved the warrant, and the FBI would have accessed the information in the user's account.
That would have been the correct way to do it.
That would have been the correct way to do it.
Whether or not we agree with the law is a separate matter from whether or not a crime was committed -- which they had reasonable suspicion to believe it was. Therefore, they should have gone in front of a judge for a warrant.