Supreme Court building

The Supreme Court ruled Monday that a mandatory 20-year sentence for drug dealers should not apply if the drug sold was only a contributing factor to a user's death. Above, the court's building in Washington. (Michael Reynolds / European Pressphoto Agency / January 13, 2014)

WASHINGTON — The Supreme Court on Monday relaxed sentencing guidelines for drug dealers, ruling they may not be given a mandatory 20-year prison term every time an overdose results in the death of a user.

In a 9-0 decision, the justices ruled that federal prosecutors must prove that the heroin, cocaine or other illegal drug actually caused the death. Previously prosecutors and most federal courts had maintained that drug dealers must be sentenced to least 20 years in prison whenever an illegal drug was a “contributing cause” in a death.

“We decline to adopt the government’s permissive interpretation,” Justice Antonin Scalia said in a decision that partly reversed the sentence of a heroin dealer from Iowa.

The ruling in Burrage vs. United States substantially revises one of the harsh mandatory sentencing provisions adopted in a 1986 “war on drugs” law. It said that when death or serious bodily injury results from the use of an illegal drug, the defendant who distributed it “shall be sentenced to a term of imprisonment which … shall not be less than 20 years” or greater than life in prison.

PHOTOS: Politics in 2014

The Justice Department, which said there were more than 205,000 deaths from drug overdoses between 1999 and 2010, had used this provision to obtain long prison terms for drug dealers.

Justices took up an appeal from Marcus Burrage, a Iowa man who pleaded guilty to selling heroin but denied he was responsible for the death of Joshua Banka.

Scalia described Banka as a “longtime drug user” who died in 2010 “following an extended drug binge.” Evidence showed he had smoked marijuana and injected oxycodone and had several other drugs in his system when he bought a gram of heroin from Burrage.

Doctors said he died of a “mixed drug intoxication” and that the heroin was one contributing factor. A federal judge and an appeals court upheld the 20-year addition to Burrage’s prison term for distributing heroin. He also received a 20-year term for selling the narcotics.

The Supreme Court reversed the extra sentence given to Burrage and said that in the future, prosecutors must show an illegal drug actually caused the death of a user.

Scalia said the “role of this court is to apply the statute as it is written.” The phrase “results in” has traditionally meant that something actually caused the harm, he said.

ALSO:

Pregnant, brain-dead Texas woman taken off life support 

Gunman in Maryland mall shooting identified; motive a mystery

Holder says plea talks possible with Snowden, but not amnesty

david.savage@latimes.com

Twitter: @davidgsavage