Sale of Firearm to a Convicted Felon

Sale of Firearm to a Convicted Felon - it is unlawful for any person to sell or dispose of any firearm or ammunition to any person knowing or having reason to believe that such person: is under indictment or been convicted of a felony; is a fugitive from justice; abuses any controlled substance; has been adjudicated as suffering from mental health issues; is an illegal alien or an alien admitted under a non-immigrant visa; has been dishonorably discharged from the Armed Forces; has renounced his or her United States citizenship; is subject to a restraining court order prohibiting harassing, stalking, or threatening an intimate partner or child; or has been previously convicted of a misdemeanor crime of domestic violence.

Source: http://www.law.cornell.edu/uscode/text/18/922