((a)) ** Examination**
((1)) ** In general** For purposes of ensuring compliance with the Customs laws of the United States and other laws enforced by the Customs Service, including the provisions of law described in paragraph (2), a Customs officer may, subject to the provisions of this section, stop and search at the border, without a search warrant, mail of domestic origin transmitted for export by the United States Postal Service and foreign mail transiting the United States that is being imported or exported by the United States Postal Service.
((2)) ** Provisions of law described** The provisions of law described in this paragraph are the following:
((A)) (relating to reports on exporting and importing monetary instruments).
((B)) Sections 1461, 1463, 1465, and 1466, and chapter 110 of title 18 (relating to obscenity and child pornography).
((C)) (relating to exportation of controlled substances).
((D)) The Export Administration Act of 1979 (50 U.S.C. App. 2401 et seq.).
((E)) .
((F)) The International Emergency Economic Powers Act ( et seq.).
((b)) ** Search of mail not sealed against inspection and other mail** Mail not sealed against inspection under the postal laws and regulations of the United States, mail which bears a Customs declaration, and mail with respect to which the sender or addressee has consented in writing to search, may be searched by a Customs officer.
((c)) ** Search of mail sealed against inspection weighing in excess of 16 ounces**
((1)) ** In general** Mail weighing in excess of 16 ounces sealed against inspection under the postal laws and regulations of the United States may be searched by a Customs officer, subject to paragraph (2), if there is reasonable cause to suspect that such mail contains one or more of the following:
((A)) Monetary instruments, as defined in .
((B)) A weapon of mass destruction, as defined in section 2332a(b) of title 18.
((C)) A drug or other substance listed in schedule I, II, III, or IV in .
((D)) National defense and related information transmitted in violation of any of sections 793 through 798 of title 18.
((E)) Merchandise mailed in violation of section 1715 or 1716 of title 18.
((F)) Merchandise mailed in violation of any provision of chapter 71 (relating to obscenity) or chapter 110 (relating to sexual exploitation and other abuse of children) of title 18.
((G)) Merchandise mailed in violation of the Export Administration Act of 1979 (50 U.S.C. App. 2401 et seq.).
((H)) Merchandise mailed in violation of .
((I)) Merchandise mailed in violation of the International Emergency Economic Powers Act ( et seq.).
((J)) Merchandise mailed in violation of the Trading with the Enemy Act (50 U.S.C. App. 1 et seq.).
((K)) Merchandise subject to any other law enforced by the Customs Service.
((2)) ** Limitation** No person acting under the authority of paragraph (1) shall read, or authorize any other person to read, any correspondence contained in mail sealed against inspection unless prior to so reading—
((A)) a search warrant has been issued pursuant to rule 41 of the Federal Rules of Criminal Procedure; or
((B)) the sender or addressee has given written authorization for such reading.
((d)) ** Search of mail sealed against inspection weighing 16 ounces or less** Notwithstanding any other provision of this section, subsection (a)(1) shall not apply to mail weighing 16 ounces or less sealed against inspection under the postal laws and regulations of the United States.