Anonymity (from the Greek ἀνωνυμία), or namelessness, is the unidentifiability of a person in a given context. Related to anonymity is pseudonymity, which entails a repeatable identification of a person but avoids that person’s real name. Anonymity and pseudonymity are beneficial or even necessary for people in many situations, such as lottery winners, victims of abuse, voters, people seeking medical or psychological aid, whistle-blowers, witnesses to serious crimes whose lives are threatened, and authors of controversial publications, as well as investigators, intelligence officers, and other government agents.
Tor helps to improve one’s level of online anonymity. Online anonymity itself is acknowledged by international documents, such as the Council of Europe’s ‘Declaration on freedom of communication on the Internet or the United Nations ‘Report of the Special Rapporteur on promoting and protecting the right to freedom of opinion and expression.’ The legality of the mere use of Tor is therefore well established.
Even though anonymity is recognized and protected by law, it would be misleading to describe it as a separate right. That is because anonymity is context-dependent. If something is legal, then doing it anonymously should also be legal; if something is illegal, it does not become legal when done anonymously. Instead, it is better to treat anonymity as an integral element in multiple human rights, such as the right to freedom of expression, the right to privacy, the right to freedom of assembly, the right to freedom of association, and the right to vote (whose exercise is actually compulsorily anonymous).
Tor has the potential to improve online anonymity in the exercise of the right to freedom of expression and in the protection of the right to privacy, which is discussed below.