As a result, evidence that a superhero obtains by breaking into a villain’s headquarters is admissible even though it was obtained illegally. See, Burdeau v. McDowell, 256 U.S. 465 (1921). And since it doesn’t invoke the fruit of the poisonous tree doctrine, any additional evidence obtained via the original evidence would also be admissible. [...]
In the real world, this would cause significant problems for Batman and Gotham. Batman’s rough and tumble style would lead to a rash of Section 1983 claims for damages and probably also for an injunction against Batman’s future cooperation in police investigations. As discussed earlier, most evidence that Batman collects would be inadmissible, and police use of that evidence might bar the use of additional evidence collected during a subsequent police investigation.
Is Batman a State Actor?