A second-class citizen is a person who is systematically and actively discriminated against within a state or other political jurisdiction, despite their nominal status as a citizen or a legal resident there. While not necessarily slaves, outlaws, illegal immigrants, or criminals, second-class citizens have significantly limited legal rights, civil rights and socioeconomic opportunities, and are often subject to mistreatment and exploitation at the hands of their putative superiors. Systems with de facto second-class citizenry are widely regarded as violating human rights.
Typical conditions facing second-class citizens include but are not limited to:disenfranchisement (a lack or loss of voting rights) limitations on civil or military service (not including conscription in every case) restrictions on language, religion, education lack of freedom of movement, expression, and association limitations on the right to keep and bear arms restrictions on marriage restrictions on housing restrictions on property ownership
The category is normally unofficial and mostly academic, and the term itself is generally used as a pejorative by commentators. Governments will typically deny the existence of a second class within its polity, and as an informal category, second-class citizenship is not objectively measured, but cases such as the Southern United States under racial segregation and Jim Crow laws, the repression of Aboriginal citizens in Australia prior to 1967, deported ethnic groups designated as "special settlers" in the Soviet Union, the Apartheid regime in South Africa, women in Saudi Arabia under Saudi Sharia law, LGBT people in countries that do not allow same-sex marriage, or outright criminalize consensual same-sex sexual relations, and Roman Catholics in Northern Ireland during the Parliamentary era are all examples of groups that have been historically described as having second-class citizenry and being victims of state-sponsored discrimination. Historically, before the mid-20th century, this policy was applied by several European colonial empires on colonial residents of overseas possessions.
A resident alien or foreign national, and children in general, fit most definitions of a second-class citizen. This does not mean that they do not have any legal protections, nor do they lack acceptance by the local population, but they lack many of the civil rights commonly given to the dominant social group. A naturalized citizen on the other hand essentially carries the same rights and responsibilities as any other citizen, except for possible exclusion from certain public offices, and is also legally protected.