Millions of people live in the US without legal status. Many arrived years ago, work, pay taxes, and have citizen children. Policy options range from broad legalization to broad removal, with numerous intermediate approaches.
A substantial share of the unauthorized population entered lawfully and remained after a visa expired, rather than crossing between ports. This shapes which enforcement tools are relevant.
Unauthorized workers pay sales and property taxes, and many pay payroll and income taxes using assigned taxpayer numbers, while remaining ineligible for most federal benefits they help fund.
Mixed-status households are common, in which citizen children live with a parent who lacks status. Enforcement decisions therefore affect citizens as well as non-citizens.