State

States were semi-autonomous regions of countries which generally had broad powers over the affairs of their residents. The national government formed by the combination of the several states was often called the "federal government". (EDA: Endgame) It was not the universal condition of governmental organisation on Earth, as some countries, like England, were not subdivided into states. Notable examples of countries that had states were the United States of America and Australia. Canada effectively had states, but called them "provinces". (TW: Children of Earth: Day Three) Amongst the things that states and provinces did was issue license plates for motor vehicles. Sarah Jane Smith, for instance, kept an Ontario license plate in her attic. (SJA: Enemy of the Bane)

United States
States were so integral to the structure of the United States of America that the concept appears in the very name of the country. States were headed by governors, who had authority over at least the penal systems. They could offer paroles to prisoners. This implied that states had their own bodies of laws and that people could be punished for breaking them. (TW: The New World)

The question of whether states could secede from the federal union was central to the American Civil War. After a long and bloody conflict, the answer to the question was determined to be "no". (TN: Blood and Hope)

Some of the states to which the Doctor or his friends and associates were known to travel included: category=American states columns=3

Australia
Less was known about the organisation of the Australian nation, and the relationship of its federal government to its states. Australian states to which the Doctor or his friends and associates were known to travel included: category=Australian states columns=3