I'm curious- has no one ever tried to sue a superhero/heroes( this applies to DC as well as Marvel Universes) Given the general litigiousness that outsiders have long noted in American life( even a sitting President was once sued in real life- Jones v Clinton- for alleged sexual harassment). True, many heroes/heroines in both universes have secret identities and their whereabouts are not known, but given that many others either have their identities(pace the FF) known or are known to congregate at a certain place( Avengers' Mansion, Baxter Building, making them easy targets for process servers.
it doesn't have to be "perps" suing for "brutality/unneccessary force"( be they supervillains or muggers/bank robbers), it can be people who were injured in the course of a battle between heroes and villains or who had their property/business wrecked in said conflagration- or just were traumatized emotionally by them( of course this plot in "The Incredibles" is why the family of superheroes has to retire after being sued to death by irate citizens).
Given the "deep pockets" doctrine and the propensity of "ambulance chasing" attorneys( who wants to sue Spider-Man, Daredevil or the Hulk who are all known to be be virtually destitute when you can "hit the jackpot " by suing the Avengers or the FF who are all known to be loaded?). In an early FF story the Sub_Mariner tries to sue the entire human race for "pain and suffering" caused allegedly by humanity to his people but his suit was dismissed on the grounds that there was no precedent for suing all of humanity( this was back in the 1960s- the law has clearly evolved since those far-off days!).
And what about the rights of foreign superheroes( if any) on American soil?