Section was classified to section 845 of this title prior to renumbering by Pub. L. 101–647.

1990—Subsec. (a). Pub. L. 101–647, § 1003(a)(1), substituted “subject to (1) twice the maximum punishment authorized by section 841 (b) of this title” for “punishable by (1) a term of imprisonment, or a fine, or both, up to twice that authorized by section 841 (b) of this title”.

Pub. L. 101–647, § 1002(a)(2)(A), substituted “section 860” for “section 845a”.

Subsec. (b). Pub. L. 101–647, § 3599L, substituted “has become final” for “have become final”.

Pub. L. 101–647, § 1003(a)(2), substituted “subject to (1) three times the maximum punishment authorized by section 841 (b) of this title” for “punishable by (1) a term of imprisonment, or a fine, or both, up to three times that authorized by section 841 (b) of this title”.

Pub. L. 101–647, § 1002(a)(2)(B), substituted “section 860” for “section 845a”.

1988—Subsec. (a). Pub. L. 100–690, § 6455, inserted at end “The mandatory minimum sentencing provisions of this subsection shall not apply to offenses involving 5 grams or less of marihuana.”

Subsec. (b). Pub. L. 100–690, § 6452(b), struck out “or subsequent” after “Second” in heading, and in text struck out “or convictions” after “a prior conviction”, and inserted at end “Penalties for third and subsequent convictions shall be governed by section 841 (b)(1)(A) of this title.”

Pub. L. 100–690, § 6456, struck out “The mandatory minimum sentencing provisions of this paragraph shall not apply to offenses involving 5 grams or less of marihuana.”

1986—Subsec. (a). Pub. L. 99–570, § 1105(a), inserted “Except to the extent a greater minimum sentence is otherwise provided by section 841 (b) of this title, a term of imprisonment under this subsection shall be not less than one year.”

Pub. L. 99–570, § 1004(a), substituted “term of supervised release” for “special parole term”.

Subsec. (b). Pub. L. 99–570, § 1105(b), inserted “Except to the extent a greater minimum sentence is otherwise provided by section 841 (b) of this title, a term of imprisonment under this subsection shall be not less than one year. The mandatory minimum sentencing provisions of this paragraph shall not apply to offenses involving 5 grams or less of marihuana.”

Pub. L. 99–570, § 1004(a), substituted “term of supervised release” for “special parole term”.

1984—Subsecs. (a), (b). Pub. L. 98–473, § 503(b)(3), substituted “Except as provided in section 845a of this title, any” for “Any”.

Pub. L. 98–473, § 224(b), which directed amendment of this section effective Nov. 1, 1987 (see section 235(a)(1) of Pub. L. 98–473 set out as an Effective Date note under section 3551 of Title 18, Crimes and Criminal Procedure) was repealed by Pub. L. 99–570, § 1005(b)(1).

Amendment by section 1004(a) of Pub. L. 99–570 effective on date of taking effect of section 3583 of Title 18, Crimes and Criminal Procedure (Nov. 1, 1987), see section 1004(b) of Pub. L. 99–570 set out as a note under section 841 of this title.