They're pre-emptively choosing to obstruct enforcement of whatever laws they deem unacceptable. So that's quite a rosy expectation about their willingness to cooperate.
I don't think you could consider this obstruction. It's their service, it's private, they can serve data to users the way they wish. There is a method and a system in place if law enforcement can prove they need unfettered access – a warrant issued by a judge.
The US has a pretty robust system for dealing with this. Get a warrant.