Victims of crime should not be given special powers. If anything, their biased position makes them less able to understand that the accused has rights, should be evaluated impartially, are presumed innocent, and shouldn't be subject to unfair punishment if proven guilty.

I'm really tired of seeing internet commentary on "tough on crime" attitudes where people think victims are basically judge and jury, possibly omniscient, and their hurt and revenge fantasies should decide policy for millions of unrelated people, supersedes the needs of everybody else, like our need to have an impartial justice system and prevent wrongful conviction.

But getting back to your comment, if you want to know where the "perverse incentive" is in your proposal, it creates incentive for someone to falsely present themselves as a victim of a crime.