A mandatory minimum sentencing statute is a law that requires a judge to impose a statutorily prescribed sentence. It is most commonly understood to mean a statute that requires imposition of a specific minimum term of imprisonment. The statutes that outlaw most federal crimes do not call for a mandatory minimum sentence. Several statutes that outlaw federal sex offenses insist upon a minimum term of imprisonment. This is a brief overview of those provisions. Mandatory minimum sentences have been with us since the dawn of the Republic. The First Congress made mandatory capital offenses of treason, murder in a federal enclave, piracy, forgery, and counterfeiting. A few years later, the Sedition and Logan Acts arrived with six- month mandatory minimum terms of imprisonment. Congress made rape committed within the maritime jurisdiction of the United States a mandatory capital offense in 1825. So the punishment remained until the 1948 recodification of federal criminal law, when rape became punishable by death or imprisonment for any term of years or for life. Congress increased the number of federal sex offenses and their attendant mandatory minimum sentences beginning in 1978 with the enactment of the first federal child pornography statutes: 18 U.S.C. 2251, 2252. It filled out the complement of federal sex offenses with mandatory minimum sentences of imprisonment at fairly regular intervals thereafter. In United States Sentencing Commission survey which addressed mandatory minimum sentences in child pornography cases but not other sex offense cases, a majority of the judges responding to a United States Sentencing Commission survey thought that the mandatory minimum sentences for production and distribution of child pornography and other child exploitation offenses were generally appropriate. Well over two-thirds, however, considered those for receipt of child pornography too high. The Commission's report on mandatory minimum sentencing statutes noted that its "review of available sentencing data [relating to sex offenses] indicates that further study of these penalties is needed before it can offer specific recommendations in this area." It concluded preliminarily, however, that "the mandatory minimum penalties for certain non-contact child pornography offenses may be excessively severe and as a result are being applied inconsistently." There may be reasonable disagreement over what constitutes a mandatory minimum sentencing statute. Even when limited to statutes that require a minimum term of imprisonment, questions may arise with respect to: (1) statutes like 18 U.S.C. 2241(c) (sexual abuse of a child) that requires offenders to be imprisoned for not less than 30 years or for life; (2) statutes like 18 U.S.C. 2242 (sexual abuse of an incapacitated victim) that requires offenders to be fined and imprisoned for any term of years or for life; and (3) statutes like 18 U.S.C. 2241(a)(aggravated sexual abuse) that requires offenders to be fined, imprisoned for any term of years or life, or both. Subsection 2241(c) certainly appears to require a mandatory minimum sentence ("imprisoned not less than 30 years"). Section 2242 also appears to require a mandatory minimum sentence, absent the dubious conclusion that the phrase, "imprisonment for any term of years" authorizes a court to impose a sentence of imprisonment for some particular number of years with the permissible choices ranging from zero to infinity. The mandatory minimum status of subsection 2241(a)("fine [or] imprisonment for any term of years") seems more debatable. The subsection can hardly be said to require a mandatory minimum sentence of imprisonment, if a court is free to impose a fine instead. Moreover, in another context, the courts have concluded that in the face of such language a court is free to impose a fine instead of a term of imprisonment. Nevertheless, it is treated as requiring a mandatory minimum sentence here, because as a practical matter a court is virtually required to impose a sentence of imprisonment following conviction for a crime as serious as a violation of subsection 2241(a). Defendants sentenced to mandatory minimum terms of imprisonment have challenged them on a number of constitutional grounds ranging from Congress's legislative authority, to cruel and unusual punishment, through ex post facto and double jeopardy, to equal protection and due process. Each constitutional provision defines the outer boundaries that a federal criminal statute must be crafted to honor. Most statutes and the penalties they impose have survived scrutiny. The federal government is a creature of the Constitution. It enjoys only such powers as can be traced to the Constitution. All other powers are reserved to the states or to the people. The Constitution grants Congress authority to enact legislation "necessary and proper" to the execution of those powers which it vests in Congress or in any officer or department of the federal government. Among the powers which the Constitution bestows upon Congress are the powers to define and punish felonies committed upon the high seas, to exercise exclusive legislative authority over certain federal territories and facilities, to make rules governing the armed forces, and to regulate interstate and foreign commerce, and to enact legislation necessary and proper for the execution of those and other constitutionally granted powers. Many of the existing federal sex offenses with mandatory minimum sentencing requirements were enacted pursuant to Congress's legislative authority over crimes occurring on the high seas or within federal enclaves, or to its power to regulate commerce. The Supreme Court has explained that under the commerce clause: "Congress may regulate the use of the channels of interstate commerce. Second, Congress is empowered to regulate and protect the instrumentalities of interstate commerce, or persons or things in interstate commerce, even though the threat may come only from intrastate activities. Finally, Congress' commerce authority includes the power to regulate those activities having a substantial relation to interstate commerce." When a statute falls for want of legislative authority, the penalties it would impose fall with it. This has yet to occur in the area of mandatory minimum sentences. The Eighth Amendment bars mandatory capital punishment statutes. And although the case law is somewhat uncertain, it seems the Amendment condemns any punishment that is "grossly disproportionate" to the misconduct for which it is imposed. A sentence imposed under a mandatory minimum federal sex offense statute might be "grossly disproportionate" to the offense under extreme circumstances, but the sentences in most cases are not. While "it remains a basic principle of our constitutional scheme that one branch of the Government may not intrude upon the central prerogatives of another," the Supreme Court has observed that "Congress has the power to define criminal punishments without giving the courts any sentencing discretion." Thus, the lower federal courts have regularly upheld mandatory minimum statutes when challenged on separation of powers grounds, and the Supreme Court found no separation of powers infirmity in the federal sentencing guideline system, a system which might have been thought to produce its own form of mandatory minimums. The Fifth Amendment due process clause embodies an equal protection component that cabins federal action in the manner that the Fourteenth Amendment equal protection clause cabins state action. Equal protection precludes punishing a defendant more severely than others similarly situated, when the distinction is based on some constitutionally suspect classification such as race or alternatively when the distinction has no rational basis. However, a defendant convicted of a federal sex crime has no equal protection claim, simply because he might have been less severely punished under state law or because he might have been charged with a less serious federal offense. Equal protection also prohibits punishment, under a facially neutral statute, that is intended to have an adverse impact on a constitutionally protected class. Yet, the presence of a rational basis for a classification will belie an intent to adversely impact. Thus, Native Americans, who may be more likely to come within the reach of federal criminal laws applicable on federal lands, have no equal protection claim as long as Congress had a rational basis for enacting such laws. Defendants whose prior convictions trigger a mandatory minimum sentencing requirement have occasionally objected on double jeopardy or ex post facto grounds. Double jeopardy bans trying or punishing a defendant twice for the same offense. Ex post facto bars retroactive criminal statutes. More precisely, the double jeopardy clause "protects against successive prosecutions for the same offense after acquittal or conviction and against multiple criminal punishments for the same offense." The ex post facto clauses, on the other hand, preclude laws that "retroactively alter the definition of crimes or [retroactively] increase the punishment for criminal acts." As the Supreme Court explained when it rejected the double jeopardy challenge to the California "three strikes" statute: Historically, we have found double jeopardy protections inapplicable to sentencing proceedings, because the determinations at issue do not place a defendant in jeopardy for an "offense," see e.g., Nichols v. United States , 511 U.S. 738, 747 (1994)(noting that repeat-offender laws "penaliz[e] only the last offense committed by the defendant"). Nor have sentence enhancements been construed as additional punishment for the previous offense; rather, they act to increase a sentence "because of the manner in which [the defendant] committed the crime of conviction." An enhanced sentence imposed on a persistent offender thus "is not to be viewed as either a new jeopardy or additional penalty for the earlier crimes" but as "a stiffened penalty for the latest crime which is considered to be an aggravated offense because a repetitive one." Monge v. California , 524 U.S. at 728 (some citations omitted). Courts confronted with ex post facto challenges to recidivist statutes have similarly focused upon the "latest crime" and not upon the first. Most of the mandatory minimum penalties for federal sex offenses appear in one of three chapters of title 18 of the United States Code. Chapter 109A outlaws rape and other forms of sexual abuse and sexual contact when committed in federal enclaves or federal prisons. Chapter 110 outlaws child pornography. Chapter 117 outlaws sexual activities that have travel or commercial attributes. Chapter 109A reaches a relatively wide range of sexual misconduct under relatively narrow jurisdiction circumstances. It applies in the special maritime and territorial jurisdiction of the United States.