We studied morality judgments on the behavior of human and artificial systems, by comparing, in a between-subjects experiment (n= 381), both the perception of the seriousness of an action causing harm to either some persons or some robots committed by either a person or a robot, and the attribution of the appropriated punishment for that action. The results showed a significant and predictable effect of the type of victim: the action was considered more a serious offence, and deemed worthy of more severe punishment, if the victims were humans than if them were robots. A significant interaction effect between type of agent and type of victim was also found on the punishment judgements: for human victims, a human agent was punished more severely than a robot, while for robot victims, a robot agent was attributed a more severe punishment than a human one. The results are discussed in the light of the theories linking moral judgments to mind perception.