Valid reasons to punish?

Does "valid reasons to punish" mean "valid reasons to be punished (for the behaviour modification and the deterrence of others)"?

Context:

One implication of a determined will, Harris says, is that it becomes unreasonable to punish people out of retribution—only behaviour modification and the deterrence of others still seem to be potentially valid reasons to punish.^[26] This, especially because behaviour modification is a sort of cure for the evil behaviours; Harris provides a thought experiment:

Consider what would happen if we discovered a cure for human evil. Imagine, for the sake of argument...the cure for psychopathy can be put directly into the food supply like vitamin D...consider, for instance, the prospect of withholding the cure for evil from a murderer as part of his punishment. Would this make any moral sense at all?^[26]