Of course they'll share it. First, non-citizens are usually even less protected than citizens. Second, secret services are also extralegal services as long as they can get away with it. Third, if they get caught, they won't be punished.

German example: The BND has been caught spying on all Germans' communication (most probably still does so), as well as connections to foreign countries. They are only supposed to watch foreign countries. So they came up with a legal theory, called "Weltraumtheorie", where satellites are in space, so outside the jurisdiction of any state. https://de.wikipedia.org/wiki/Weltraumtheorie Later on, when this got out, it was just legalized and extended to fibre connections, because, well, that just replaces space, doesn't it?...