From the Document: "The Immigration and Nationality Act (INA) governs the admission, removal, and presence of non-U.S. nationals (aliens). Congress has established criminal sanctions for certain conduct that undermines immigration rules. Immigration-related cases make up a significant portion of the federal criminal caseload. 'See' U.S. SENTENCING COMMISSION, FISCAL YEAR 2018 OVERVIEW OF FEDERAL CRIMINAL CASES 12 (2019). Immigration-related crimes generally cover three categories of conduct: (1) improper entry and reentry; (2) the smuggling, transporting, and harboring of aliens; and (3) immigration-related fraud."
CRS In Focus, IF11410
Congressional Research Service: https://crsreports.congress.gov/