True, overstaying a tourist, student, or guest worker visa or remaining after an asylum claim is denied - typically doesn’t trigger criminal charges under U.S. law. It’s classified as a civil violation leading to deportation proceedings. However, this doesn’t make it legal. The Immigration and Nationality Act (INA) defines such individuals as 'unlawfully present' (8 U.S.C. § 1182(a)(9)(B)), meaning their status violates federal immigration law.
the act of illegal entry into the United States is explicitly a federal crime under 8 U.S.C. § 1325. This statute makes it a misdemeanor to enter or attempt to enter the U.S. at a time or place other than as designated by immigration officers, or to elude examination or inspection by immigration officials. A second offense can even escalate to a felony. Therefore, while unlawful presence alone may not be a crime, the initial act of entering without authorization is