The state appealed to the Supreme Court. The justices said they would decide whether Hoffman is entitled to the plea deal, even though he was later convicted and sentenced in a fair trial.

Hoffman was one of three men charged with the murder of a woman who served as a police informant in a drug deal. Hoffman slit Denise Williams' throat and another man stabbed her. Both men tried to bury her beneath rocks, eventually killing her with a blow from a rock.

The other two defendants avoided the death penalty. Hoffman, however, refused to plead guilty on the advice of his attorneys, even though prosecutors told him that if he refused the plea deal they would seek the death penalty.

One of Hoffman's attorneys — William Wellman — told Hoffman he believed that a recent appellate court ruling out of Arizona showed that Idaho's similar death penalty scheme was unconstitutional, and that it was only a matter of time before Idaho's death penalty scheme would be overturned in court.

But Idaho's death penalty scheme wasn't immediately overturned, and on June 9, 1989, Hoffman was sentenced to death.

The appeals court said Wellman made two mistakes that warranted overturning the death sentence.

"We do not expect counsel to be prescient about the direction the law will take," Judge Harry Pregerson wrote for the three-judge panel. "We nonetheless find that Wellman's representation of Hoffman during the plea bargaining stage was deficient for two reasons: first, Wellman based his advice on incomplete research, and second, Wellman recommended that his client risk much in exchange for very little."

That error, combined with Hoffman's compliant personality, meant that he was harmed by the attorney's recommendation, the court found.

Idaho's lawyers told the Supreme Court that the 9th Circuit made it too easy for defendants to prove that their lawyers were ineffective. The decision shouldn't turn on whether the advice was right or wrong, but on whether a competent lawyer would have made the same recommendation, the state said.