The existence of costumed heroes raises interesting questions about the legality of being a superhero. Specifically, issues regarding the privacy of a secret identity vs. constitutional rights of suspected criminals to be able to address their accusers.
The identity of a registered hero is regulated by the Department of Extranormal Operations as part of their registry of metahumans. A registered identity comes with a state-issued ID that is accepted as proof of identity by state governments. This allows vigilantes to provide ID to law enforcement, make a witness statement, or obtain goods and services related to their work as a vigilante.
However, this means a vigilante is working as an actor on behalf of the state. This complicates many factors that contribute to criminal prosecution, such as warrantless entry or gathering evidence obtained while working as an actor. Evidence uncovered during actions that violate constitutional rights of criminals may be inadmissible as evidence, even if turned over to the district attorney's office. This requires DAs to build cases based solely on the evidence and testimony of their own officers and with whatever evidence they recover.
In some cases, use of metahuman talents to stop misdemeanour offenses can be problematic as well-- a citizen may only make a citizen's arrest if a felony has occurred and may not use lethal force to do so unless someone is in imminent danger of death or injury. Unlawful detention may result in criminal charges against the intervening individual. Possession of illegally confiscated goods, whether cash or paraphernalia, may result in additional charges for the individual acting as a vigilante. If a vigilante has been given goods or equipment that facilitate their actions, the donor of those items can be held liable in civil and even criminal court for the actions of the recipient.
Crucially, statutory law requires that an accused citizen be able to face their accuser in court. Vigilante identities are not acceptable when delivering testimony, either verbally or by affidavit. A vigilante who testifies in court must unmask and use their legal name to do so. This has resulted in many cases being dismissed due to the state being unable to produce the primary witness who can relate the scope of criminal activities and establish the chain of custody of evidence.