	Introduction

The United States Supreme Court in United States v. Comstock held that Congress possessed the legislative authority under the Constitution's necessary and proper clause to enact 18 U.S.C. Legislative Authority

The Constitution vests federal legislative powers in Congress. Those legislative powers which it does not mention are reserved to the states and the people. When it framed the issue, however, it eluded the role of the Necessary and Proper Clause: "The question presented in this case is whether the power vested in Congress by Article I, §8, of the Constitution, '[t]o make all Laws which shall be necessary and proper for carrying into Execution' its authority to 'regulate Commerce with Foreign Nations, and among the several States.'" "Pursuant to its power under the Necessary and Proper Clause, Congress has carried into execution various of its enumerated powers—... U.S. Const. Section 4248, it contended, "is a rational incident to Congress' Article I powers to enact criminal laws, provide for the operation of a penal system, and assume for the United States custodial responsibilities for its prisoners." United States v. Comstock

The Court in United States v. Comstock adopted the Justice Department's sequential or stepping stone argument, up to a point. The Court agreed that the Necessary and Proper Clause permits Congress to create federal criminal laws to ensure compliance with legislation enacted pursuant to one of its enumerated powers. 158 (1855); "(3) the sound reasons for the statute's enactment in light of the Government's custodial interest in safeguarding the public from dangers posed by those in federal custody" should they be released when other grounds for federal detention ceased to exist; "(4) the statute's accommodation of state interests" by affording states the option of assuming treatment responsibility for those of its citizens civilly committed under Section 4248; "and (5) the statute's narrow scope," that is, civil commitment of sexually dangerous individuals otherwise scheduled for release from federal custody. Had the views of Justices Thomas and Scalia prevailed, there might have been some question of the continued validity of federal statutes which permit civil commitment on other mental grounds of federal prisoners scheduled for release or of other statutes which permit imposition of a term of supervised release to be served after federal inmates are released from prison. Five members of the Court, however, obviously found more appropriate a more nuanced description of the scope of the Clause—sometimes, the Necessary and Proper Clause will support legislation to help carry into execution a power which itself is no more than necessary and proper. The extent to which the Court's five considerations will be found to limit the stepping stone reach of the Clause in the future remains to be seen.
The Adam Walsh Act created 18 U.S.C. 4248, which authorizes civil commitment as sexually dangerous those otherwise about to be released from federal custody. In United States v. Comstock, the United States Supreme Court rejected a suggestion that enactment of Section 4248 lay outside the scope of Congress's legislative powers. It did so without considering whether the section might be vulnerable to constitutional attack on other grounds.
The Constitution reserves to the states and the people those powers that it does not vest in the federal government. It vests in Congress the authority to enact laws necessary and proper to carrying into execution the powers it bestows on the federal government. The Justice Department contended that Congress has authority under the Constitution to enact those criminal laws which it finds necessary and proper to carry into execution various of its other powers such as the regulation of interstate and foreign commerce and legislation for the District of Columbia and federal enclaves. It argued further that incident to the power to enact criminal laws is the power to enact laws for the operation of a federal penal system and for responsibility for those assigned to that system, even after the expiration of the initial authority to imprison them.
Comstock argued that Congress has no such incidental power. He contended that Congress's constitutional authority to enact legislation with respect to those imprisoned for violation of federal criminal laws ends with their terms of imprisonment. Subject to certain conditions that might lead to a different result under other circumstances, the Court agreed with the Justice Department, up to a point.
Had Comstock prevailed, there might have been some question of the continued validity of federal statutes which permit civil commitment on other grounds of federal prisoners scheduled for release or of those statutes which permit imposition of a term of supervised release to be served after federal inmates are released from prison.
As is, the opinion appears to support a more expansive view of Congress's legislative authority than was previously the case—sometimes, the Necessary and Proper Clause will support legislation to help carry into execution a power which itself is no more than necessary and proper.
The Court's conclusion in Comstock was predicated upon "(1) the breadth of the Necessary and Proper Clause ... , (2) the long history of federal involvement in this area, (3) the sound reasons for the statute's enactment in light of the Government's custodial interest in safeguarding the public from dangers posed by those in federal custody, (4) the statute's accommodation of state interests, and (5) the statute's narrow scope," 130 S.Ct. at 1965.
The extent to which absence of such factors will be found to limit the reach of the Clause in the future remains to be seen.