Signal is open source. They absolutely do always comply with US warrants. They have never provided any information to US law enforcement, because they can't access it. They literally have no way of accessing the information contained inside the texts. The most they could provide is metadata, but they currently aren't collecting that. I also think if they started, it would not work well for their user base. You can see all their requests for information, and the responses they gave, here: https://signal.org/bigbrother/

[–] teri@discuss.tchncs.de 2 points 50 minutes ago

I really hope they stand strong. We need some influential entities standing up to the shit going on. Sadly, given the current situation in the US I have to assume that the Trump gang will sooner or later try to crack down on Signal. Who knows, forcing them to give out meta data to identify dissidents etc.

At least the open-source app makes me hope that there's a little less nasty things they can do than Facebook/Whatsapp.