Stop Illegal Trafficking in Firearms Act of 2013 - (Sec. 3) Amends the federal criminal code to prohibit any person, other than a licensed firearms importer, manufacturer, collector, or dealer (licensed dealer), from knowingly purchasing in interstate or foreign commerce (including through receipt on consignment or by way of pledge or pawn as security for payment) a firearm from a licensed dealer, or from any person who is not a licensed dealer, for another individual, knowing or having reasonable cause to believe that such individual meets specified criteria disqualifying such individual from possessing a firearm. Sets forth an enhanced penalty for such a violation committed knowing or with reasonable cause to believe that any firearm involved will be used to commit a crime of violence. Specifies exceptions for purchases for certain bona fide gifts or for a bona fide winner of an organized raffle, contest, or auction.
Prohibits: (1) transferring two or more firearms to, or receiving two or more firearms from, a person in interstate or foreign commerce knowing or with the reasonable belief that such transfer, possession, or receipt would violate a federal law punishable by a term of imprisonment exceeding one year; or (2) attempting or conspiring to commit such conduct. Authorizes an enhanced penalty for someone who organizes or supervises such conduct.
Subjects: (1) property derived from or used to commit such an offense to forfeiture, and (2) a person who derives profits from such an offense to a fine equal to twice such profits.
Includes such offenses: (1) among offenses for which wiretapping may be authorized, (2) within the definition of "racketeering activity," and (3) within the definition of "specified unlawful activity" for purposes of money laundering violations.
Directs the U.S. Sentencing Commission to review and amend its guidelines and policy statements to: (1) ensure that persons convicted of offenses involving straw purchases of firearms and firearms trafficking are subject to increased penalties; and (2) reflect congressional intent that a person convicted of such offense who is affiliated with a gang, cartel, or organized crime ring should be subject to higher penalties.
(Sec. 4) Amends the Brady Handgun Violence Prevention Act to prohibit the sale or other disposition of a firearm or ammunition knowing or having reasonable cause to believe that the purchaser intends: (1) to sell or otherwise dispose of it to a person in a category of individuals excluded from firearms possession, (2) to sell or otherwise dispose of it in furtherance of a crime of violence or drug trafficking offense, or (3) to export it in violation of law.
(Sec. 5) Increases the maximum term of imprisonment for violating prohibitions against: (1) selling firearms or ammunition to any person knowing or having reasonable cause to believe that such person is disqualified from possessing such firearms or ammunition; (2) any such disqualified person transporting or possessing any firearm or ammunition in interstate or foreign commerce or receiving any firearm or ammunition that has been has been transported in interstate or foreign commerce; (3) receiving or transferring a firearm or ammunition knowing or having reasonable cause to believe that it will be used to commit a crime of violence, a drug trafficking crime, or other specified crimes under the Arms Export Control Act, the International Emergency Economic Powers Act, the Foreign Narcotics Kingpin Designation Act, or the Immigration and Nationality Act; or (4) smuggling into or out of the United States a firearm or ammunition with intent to engage in or promote conduct that is punishable under the Controlled Substances Act, the Controlled Substances Import and Export Act, or maritime drug law enforcement provisions or that constitutes a crime of violence.
(Sec. 8) Prohibits the Department of Justice (DOJ) and any of its law enforcement coordinate agencies from conducting any operation where a federal firearms licensee is directed or encouraged to sell firearms to an individual if DOJ or a coordinate agency knows or has reasonable cause to believe that such individual is purchasing such firearms on behalf of another for an illegal purpose, unless the Attorney General, the Deputy Attorney General, or the Assistant Attorney General for the Criminal Division approves the operation in writing and determines that the agency has prepared an operational plan to prevent firearms from being transferred to third parties without law enforcement taking reasonable steps to lawfully interdict those firearms.