Convictions for relatively minor offenses can be overlooked by US immigration under the “petty offense” exception. More serious convictions, particularly those involving “moral turpitude” such as convictions involving drugs, violence, or prison sentences of more than 6 months will often require a waiver and the most serious offenses, known as “aggravated felonies” may make it impossible to obtain a visa because the waiver may be unavailable.
Convictions Involving Moral Turpitude (CIMT) will often result in immigrants being placed in removal (deportation) proceedings. This may include convictions dating back many years and it may target permanent residents who have lived in the U.S. many years and have extensive family and business ties. Often the immigrant will trigger the deportation proceedings by traveling abroad or applying for naturalization.
Waivers involving criminal convictions are among the most complicated immigration issues under the law and will always require the expertise of a knowledgeable and experienced immigration attorney. This may require working with your criminal attorney even before a plea is entered. A successful defense will often depend on various factors, including the nature of the crime, the availability of close relatives and many discretionary factors including medical, financial and other hardships.