Humans make decisions jointly with others. They share responsibility for the outcome with their interaction partners. Today, more and more often the partner in a decision is not another human but, instead, a machine. Here we ask whether the type of the partner, machine or human, affects our responsibility, our perception of the choice and the choice itself. As a workhorse we use a modified dictator game with two joint decision makers: either two humans or one human and one machine. We find no treatment effect on perceived responsibility or guilt. We also find only a small and insignificant effect on actual choices.