This provocation is great because it hits on a value that practically everyone holds but rarely evaluates. If a crime is committed (common law), what would you do? You saw it and you know the crime was committed, so why would you need validation from third parties who have nothing to do with the crime to carry out your justice? We outsource the collection of debts owed to us to criminals without even questioning it, as if they had a title of ownership over you. Larken's provocation here is good: would it be morally valid for you to take justice into your own hands? If it weren't, then you agree to let the convicted criminals of the ruling class—who decide and govern the legal system—go free.