And only sometimes. Other times he was a political campaigner. "Hey Don Jr, let's talk and coordinate the release of a bunch of DNC material when it can most benefit your dad's campaign. And don't worry, I'm sitting on the RNC material, it's safe."
It absolutely is. But there are dozens or more comments here about how Assange and Wikileaks were "above all that", and "impartial sources, without fear or favor".
When no, he was and is as partisan as anyone else.