Free Will Denial, Punishment, and Original Position Deliberation

I defend a deontological social contract justification of punishment for philosophers who deny free will and moral responsibility (FW/MR). Even if nobody has FW/MR, a criminal justice system is fair to the people it targets if we would consent to it in a version of original position deliberation where we assumed that we would be targeted by the justice system when the veil is raised. Even if we assumed we would be convicted of a crime, we would consent to the imprisonment of violent criminals if prison conditions were better than the state of nature but deterring enough to prevent the state of nature.