Modern law has developed based on the fundamental principle of respecting each person as an autonomous individual. However, the meaning of autonomous is not necessarily unambiguous even in jurisprudence, which has resulted in its use in various contexts. In this chapter, I examine the differences between personal autonomy and machine autonomy. Then I attempt to reconstruct the concept by exploring legal issues concerning privacy and freedom of expression when people use robots. As this chapter discusses, personal autonomy and machine autonomy differ considerably from each other, even when using the same concept of autonomy. Given the state of human–robot interaction (HRI) technology, it is appropriate to understand machine autonomy as having instrumental value as a means of serving personal autonomy. Furthermore, it is argued that the development of HRI will likely call for the implementation of a system of checks and balances among multiple robots to ensure autonomy as collective self-regulation for groups of robots connected to each other through information communication networks, rather than ensuring the autonomy of individual robots.