WHEN THE House of Representatives takes up the juvenile justice bill next week, it apparently will be called upon to consider an amendment by Judiciary Committee Chairman Henry Hyde (R-Ill.) to provide criminal penalties for the sale to children of "any picture, photograph, drawing, sculpture, video game, motion picture film, or similar visual representation or image, book, pamphlet, magazine, printed matter, or sound recording containing explicit sexual or violent material."

The notion is that the ban would be constitutional because the Supreme Court has said that obscenity can be constitutionally regulated, and violent material -- some of it -- no less than sexual material can fairly be categorized as obscene. But that's a stretch -- if the sale of violent material can be barred, you wonder what else can -- and Congress, assuming it should venture into this area at all, surely ought not do so by voting on an unexamined floor amendment to an altogether separate bill.

That is not to be dismissive of the problem of children's exposure to violent material that may well be -- often is -- unsuitable. Policy is patchy. Children in theory are discouraged from watching at movie theaters R-rated films that they can readily rent at local video stores. The sale of pornography to youngsters is regulated, while video games of truly stunning violence can be sold with no consequences. The impulse to imagine ways to give parents more control over what their children see and hear is not a bad one.

But criminal law is too blunt an instrument for this purpose and raises the usual -- and serious -- First Amendment problems. Graphic violence is a feature of some of our finest movies; who defines how much and what kind to ban? Who decides which film or video game does or doesn't meet the definition? Better to look to voluntary models -- the motion picture rating system, the V-chip and Internet filtering software. Some video distributors have pledged not to rent R-rated films and comparable video games to children without parental consent. That's fine. The enormous market power of consumers who care about this issue can be a more powerful tool than any legislation. It is also worth exploring whether technical features in video players and game machines that offer adults control over what videos their children can see and what games they can play are practical. Again, if consumers demand such techn

ologies, they will get them. This is a Congress that ought not have to be urged to trust the market, not the courts.