The Supreme Court said Wednesday that state courts may apply its rulings to old cases, opening the way for an imprisoned child sex abuser to challenge his conviction.

Stephen Danforth is serving a 26-year prison sentence in Minnesota for sexually abusing a 6-year-old boy. The jury at Danforth's trial in 1996 saw and heard a videotaped interview with the child. But he did not testify at the trial, so Danforth never had a chance to cross-examine him.

The Supreme Court ruled in 2004 that the Constitution requires that defendants have the right to question their accusers. But the court said last year that federal courts could apply the 2004 decision to new and pending cases, but not to older ones.

This case concerns whether state courts must follow that same rule or are free to consider older cases under the 2004 decision. The Minnesota Supreme Court said its hands were tied.

By a 7-2 vote, however, the U.S. high court said that state courts are not bound by the same limits that apply to federal courts.

A state "should be equally free to give its citizens the benefit of our rule in any fashion that does not offend federal law," Justice John Paul Stevens wrote for the court. Chief Justice John Roberts and Justice Anthony Kennedy dissented.

By the same token, Stevens said, the Minnesota court is free to turn down Danforth again, but on a different basis.