Spoiler alert: This post contains spoilers for the television show Jessica Jones.

The Netflix television series Marvel’s Jessica Jones concerns a woman with some unspecified degree of superpowers, who, after an abortive attempt at superheroing, becomes a private detective.

Her powers mostly enable her to get better angles for photographing the infidelities she’s typically hired to investigate, and to not worry much about getting beaten up. This seems to stand in stark contrast to the Parker Principle: with great power comes great responsibility.

Peter Parker (a.k.a. Spider-Man) decided that he had a moral obligation to put his powers to the best possible use helping people. We can defer to another time a discussion of the validity of the Parker Principle; for present purposes it is sufficient to see how this contrasts with Jessica’s approach. She has the cynical attitude and heavy drinking problem often associated with the hard-boiled private eye, and is content to put her powers to minimal use in the course of her cases.

But first impressions can be deceiving. As the 13-episode series progresses, we learn more and more about how Jessica came to be who and how she is. Most significantly, she is suffering from post-traumatic stress disorder and carrying around tremendous guilt as a result of her enslavement to The Purple Man (a.k.a. Kilgrave). Kilgrave’s power is mind control, and he had held Jessica in thrall for a period of time during which he made her commit crimes, including murder. While she was eventually able to escape his control (and later realized she has become immune), she has been considerably damaged psychologically by the experience, and this turns out to be at least a partial explanation for her hard-boiled demeanor and her rejection of the Parker Principle.

As the series opens, Kilgrave seems to have vanished, but he returns and insinuates himself back into Jessica’s life. He has a stalker-level obsession with her, and his plan involves making a young woman, Hope, murder her parents. Jessica becomes determined to help Hope. Many observers of the series saw it as a plot-hole that Jessica didn’t simply shoot Kilgrave with a sniper’s rifle from beyond his mind-control range, but this is to overlook Jessica’s primary motivation.

Hope is facing life in prison for the murder of her parents, so the only way Jessica can help her is by capturing Kilgrave and obtaining evidence that mind-control is real. This would prove that Hope is not responsible. Of course, to get evidence like that, Jessica has to do things that aren’t quite kosher in terms of normal rules of evidence and criminal investigation. One of the interesting things about genres such as science-fiction, fantasy and superheroes is the ways they force us to reconsider why we have the rules we have and how universally they’d apply if the world were different. If someone had Kilgrave’s mind-control power, you couldn’t even arrest and interrogate him, let alone try him in open court.

In order to obtain the exculpatory evidence she needs, Jessica has to drug him and imprison him in a hermetic chamber (his power doesn’t work over the phone or a speaker), and videotape him using mind-control. None of this would be admissible in the real world, and for good reason, but if we had people like Kilgrave around, would we need to adapt our legal systems to accommodate them?

Given the evolutionary nature of the common law, I suspect the answer is yes. We might end up with a corollary to the Parker Principle such as “with great power comes different rules of evidence.”

Not very catchy, but definitely a necessity in an evolving legal order.