It is recommended that you contact the American Consulate or Embassy closest to you before traveling to the United States. It is the sole responsibility of the Department of Homeland Security (DHS) at the port of entry to admit foreign citizens into the United States. A criminal record is a reason to deny entry. You may be required to apply for a visa waiver. The application form required is Form I-192, “Advance Permission to Enter the United States.” Several months may be required to process the application. Even though you may have entered the United States without hindrance in the past, you could run into difficulty, if your record shows a criminal conviction.

See also…

Immigration Law