The unauthorized or undocumented resident immigrant population is defined as all foreign-born non-citizens who are not legal residents. Most unauthorized residents either entered the United States without inspection or were admitted temporarily and stayed past the date they were required to leave.

Unauthorized residents applying for adjustment to lawful permanent resident (LPR) status under the Immigration and Nationality Act (INA) are unauthorized until they have been granted lawful permanent residence (a green card)—even though they may have been authorized to work. Persons who are beneficiaries of Temporary Protected Status (TPS) are not technically unauthorized.

In Rhode Island, as in all states, the definition and treatment of unauthorized or undocumented resident immigrants are primarily governed by federal law, specifically the Immigration and Nationality Act (INA). Unauthorized immigrants are those who have entered the United States without proper inspection or have overstayed their visas. These individuals do not have legal status, although they may live, work, or go to school in the state. Those applying for an adjustment to lawful permanent resident (LPR) status are considered unauthorized until they are granted a green card. However, it's important to note that individuals with Temporary Protected Status (TPS) are provided temporary relief from deportation and are authorized to work in the U.S., but they are not considered lawful permanent residents. Rhode Island state law does not override federal immigration law but may have policies affecting how state agencies interact with the unauthorized immigrant population.