The Empire of Tarsis requires all citizens to carry identification papers. Display of these papers, which the Empire issues to all citizens, is required for purchases over 100 gp. Guards and other officials also can demand to see one’s papers at any time. Identification papers include a person’s name, race, place of birth, current residence, occupation, and a general physical description. Forgeries are fairly common.
Almost all humans within the Empire automatically become citizens at birth. This is also true of most dwarves and many elves. It is more difficult, but not impossible, for members of other races to gain citizenship status; they are not automatically citizens. Citizens enjoy legal rights that noncitizens do not, as well as greater protection under the law.
More information on Imperial Citizenship.