It makes a difference whether punishment is zero-sum or negative-sum. If we can’t take $100 from Bob to give to someone else but can only impose $100 of cost on him to no one’s benefit, we’d rather not do that.
In that case I think the answer is to forego the punishment if you’re sufficiently confident the harm is an inevitable result of a net-good decision.
It makes a difference whether punishment is zero-sum or negative-sum. If we can’t take $100 from Bob to give to someone else but can only impose $100 of cost on him to no one’s benefit, we’d rather not do that.
In that case I think the answer is to forego the punishment if you’re sufficiently confident the harm is an inevitable result of a net-good decision.