Interesting stuff to think about.
It doesn't apply as easily in something like Superman Returns, where it's a bit of a standalone situation, but in the comic-book DC universe there seems to be kind of a default assumption that Bruce Wayne tends to pick up the tab for a lot of stuff (certainly for Justice League-related situations). Whether that's Bruce funneling cash through various sources on the DL, or perhaps even directly and publicly giving the Justice League an endowment via the Wayne Foundation, he seems to be pretty happy to foot the bill.
As far as legal liabilities go, yeah, a lot of the time (certainly in the Silver Age) there is talk of Superman having been freely granted legal authority to act by a variety of Federal or local agencies (I seem to recall that in the pre-Crisis era that Superman had been given honorary citizenship in every nation on Earth, or something to that effect, which seems to cover any worries about him being an 'illegal alien'). Various incarnations of the Justice League have been said to have some kind of official sanction of the UN as a peacekeeping organization, as well, and I assume that to some degree that UN member nations will recognize that authority.
In Batman's case, in different interpretations he's said either to have been formally deputized by the Gotham City Police Department or simply to be an illegal vigilante unofficially tolerated by same. So on the one hand I guess he'd be subject to the same protections as any police officer, whereas on the other it'd be a matter of, "You wanna sue Batman? Fine, we'll add that to the list." Ultimately, it'd be a matter of having to catch him first.
--g
It doesn't apply as easily in something like Superman Returns, where it's a bit of a standalone situation, but in the comic-book DC universe there seems to be kind of a default assumption that Bruce Wayne tends to pick up the tab for a lot of stuff (certainly for Justice League-related situations). Whether that's Bruce funneling cash through various sources on the DL, or perhaps even directly and publicly giving the Justice League an endowment via the Wayne Foundation, he seems to be pretty happy to foot the bill.
As far as legal liabilities go, yeah, a lot of the time (certainly in the Silver Age) there is talk of Superman having been freely granted legal authority to act by a variety of Federal or local agencies (I seem to recall that in the pre-Crisis era that Superman had been given honorary citizenship in every nation on Earth, or something to that effect, which seems to cover any worries about him being an 'illegal alien'). Various incarnations of the Justice League have been said to have some kind of official sanction of the UN as a peacekeeping organization, as well, and I assume that to some degree that UN member nations will recognize that authority.
In Batman's case, in different interpretations he's said either to have been formally deputized by the Gotham City Police Department or simply to be an illegal vigilante unofficially tolerated by same. So on the one hand I guess he'd be subject to the same protections as any police officer, whereas on the other it'd be a matter of, "You wanna sue Batman? Fine, we'll add that to the list." Ultimately, it'd be a matter of having to catch him first.
--g