Necessary and proper?

Article 1, section 8 of the Constitution gives Congress the power, “to make all laws which shall be necessary and proper for carrying into execution” a list of powers. Supreme Court nominee Elena Kagan argued recently that this gives the government the right to continue to imprison someone past his or her release date when he or she still poses a threat to society.
This week, the Supreme Court agreed with that argument, 7-2, drawing three conservative justices to a majority that essentially expands the power of the federal government by upholding a civil commitment law. But it happens to be the right decision. (Read the entire decision here. Read a news story about it here.)

Graydon Comstock was convicted of possessing child pornography. He served his 37-month sentence, but former U.S. Attorney General Alberto Gonzalez said he still posed a danger and should remain incarcerated. Lower courts disagreed, saying the government was exceeding its authority. Now the high court has overturned those rulings.
I view this the same as state laws requiring sex offenders to remain on a public registry even though they have served their time. Sure, those registries might provide a false sense of security to a parent who keeps her children away from the pervert down the street but doesn’t realize Uncle Fred is secretly a child molester. But it is a tool with which to help protect the most vulnerable among us.
Justice Samuel Alito wrote that the law is constitutional because “it is necessary and proper for Congress to provide for the civil commitment of dangerous federal prisoners who would otherwise escape civil commitment as a result of federal imprisonment.”
Reasonable minds may disagree on this one. The standard for proving someone should remain in prison is a bit lower than “clear and convincing” evidence. But I feel better knowing someone likely to repeat a sexual offense will stay off the street.