On a very narrow holding and without reaching or deciding
any claim that the statute or its application denies equal protection of the laws, procedural or substantive due process, or any other rights guaranteed by the Constitution the Supreme Court held that Congress had the authority to enact the statute. In deciding so the Court considered
(1) the breadth of the Necessary and Proper Clause,
the long history of federal involvement in this arena,
the sound reasons for the statute’s enactment in lightof 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.
So as it can be seen this is a two-tiered process; first the Court decides whether Congress is even authorized to enact this law, which the Court said it was, and second whether the law infringes on the Constitution. That question was left open for another day.
How does this case affect civil commitments in Minnesota? Legally it does not. The constitutionality of these State statutes has been already litigated and in Kansas v. Hendricks, 521 U.S. 346 (1997), the Court upheld the Kansas statute against substantive due process, double jeopardy, and ex post facto challenges, recognizing that “States have in certain narrow circumstances provided for the forcible civil detainment of people who are unable to control their behavior and who thereby pose a danger to the public health". A few years later, when addressing a Washington State program, the Court again emphasized that states have “an interest in protecting the public from dangerous individuals with treatable as well as untreatable conditions.” Seling v. Young,531 U.S. 250, 262 (2001). Likewise the Minnesota Statutes have also been held constitutional.
From a practical point of view States have a great interest in the Federal Government having a sex offender civil commitment program. With costs running in the $64,000.00 per year per person, the states are eager to share some of those costs with the federal government, because until the federal program was enacted they were shouldering this burden alone. Now they now longer have to do so.