Could be that. They seem to be justifying what they do with utilitarian reasoning. Maybe he's decided that he can do more good controlling the underworld and reigning in excesses of violence, and has no problems doing it as a traitor blackmailing the police to use their vast resources. After all, these guys are all criminals already, so why be constrained by staying as an officer of the law? If the law doesn't matter for getting the job done, why not take the logical next step and do it as real yakuza instead of as criminal police, if the ends justify the means?
With so little info to go on, the possibilities are many.