An act-based sanction punishes actions independently of the actual occurrence of harm. On the opposite, harm-based sanctions are imposed when harm occurs. When harm is certain, the distinction between act-based and harm-based sanctions is not relevant. On the opposite, when harm is probable, it is worth distinguishing act and harm based sanctions. In a basic public law enforcement framework, optimal deterrence can be achieved by both types of sanctions. This statement does not hold when potential offenders either have limited assets or are risk adverse or can invest in avoidance activities. Again, this assertion is not true when punishment is costly.