Jan. 17 (Bloomberg) -- The U.S. Supreme Court, bolstering the right-to-die movement, ruled that the Bush administration overstepped its authority by trying to block an Oregon law that authorizes doctor-assisted suicide.

The justices, voting 6-3, today said the Justice Department can't use the U.S. Controlled Substances Act to bar physicians from prescribing lethal doses of drugs to terminally ill patients, as Oregon law permits. Chief Justice John G. Roberts Jr., in his first dissent, sided with the Bush administration.

The ruling is a major victory for assisted-suicide advocates, preserving a first-of-its-kind law that both supporters and opponents say may serve as a model for other states. More than 200 people have killed themselves using drugs prescribed under the Oregon Death With Dignity Act, which took effect in 1997.

The Bush administration position would ``effect a radical shift of authority from the states to the federal government to define general standards of medical practice in every locality,'' Justice Anthony Kennedy wrote for the court.

Justices Sandra Day O'Connor, Stephen Breyer, John Paul Stevens, Ruth Bader Ginsburg and David Souter voted with the majority.

Roberts in Dissent

Roberts joined Justices Antonin Scalia and Clarence Thomas in dissent. Scalia's opinion for the group said the court should have deferred to the Justice Department, which said assisting suicide wasn't a ``legitimate medical purpose,'' as a 1971 regulation requires.

``If the term `legitimate medical purpose' has any meaning, it surely excludes the prescription of drugs to produce death,'' Scalia wrote.

The Death With Dignity Act lets doctors prescribe lethal drugs for an Oregon resident who has an incurable disease, is likely to die within six months and is mentally competent. A second physician must confirm the diagnosis. Doctors can only prescribe the drugs, not actually administer them.

Oregon voters approved the measure twice, in 1994 and 1997, the second time with 60 percent favoring the law. Court challenges kept the law on hold until October 1997.

In 2001 then-Attorney General John Ashcroft reversed a decision by his Democratic predecessor, Janet Reno, and issued a directive saying that physicians who facilitated suicide by prescribing drugs would violate the Controlled Substances Act.

1970 Law

Kennedy today said that interpretation couldn't be squared with the language of the 1970 law.

``In the face of the CSA's silence on the practice of medicine generally and its recognition of state regulation of the medical profession, it is difficult to defend the attorney general's declaration that the statute impliedly criminalizes physician-assisted suicide,'' Kennedy wrote.

Kennedy's decision focused only on the Justice Department's authority under federal drug laws and didn't directly address the more sweeping question of whether the federal government may constitutionally thwart a state that wants to allow assisted suicide.

In his dissent, however, Scalia said the federal government has authority to trump a state's wishes on assisted suicide, even as he acknowledged that power wasn't specifically enumerated in the Constitution.

``Unless we are to repudiate a long and well-established principle of our jurisprudence, using the federal commerce power to prevent assisted suicide is unquestionably permissible,'' he said.

The high court in 1997 unanimously said states can make it a crime to help someone commit suicide.

Ruling Hailed

Today's decision ``is a historic milestone that will protect the people's rights as patients,'' said Peg Sandeen, executive director the Death with Dignity National Center, an Oregon group that helped defend the law. She said in a statement that Congress may now try to pass new legislation banning doctor-assisted suicide.

Oregon Attorney general Hardy Myers also defended the law, along with a doctor, a pharmacist and two terminally ill patients.

Jay Sekulow, chief counsel of the Washington-based American Center for Law and Justice called the ruling a ``disturbing and dangerous decision that can only lessen the value of protecting human life.'' Sekulow's group supported the Bush administration in the case.

Oregon sued to challenge the directive in 2001. The San Francisco-based 9th U.S. Circuit Court of Appeals ruled 2-1 that Ashcroft had overstepped his authority, setting up the Supreme Court fight.

The case is Gonzales v. Oregon, 04-623.

To contact the reporter on this story: Greg Stohr in Washington at gstohr@bloomberg.net.

Last Updated: January 17, 2006 12:56 EST