WASHINGTON (Reuters) - The Supreme Court appeared narrowly divided on Monday on whether to overrule an 11-year-old precedent that lets judges, rather than juries, conduct fact-finding that could result in longer minimum sentences.
A review of the 2002 decision, Harris v. U.S., came in one of two cases heard by the court involving the right to a speedy and public trial by an impartial jury guaranteed by the U.S. Constitution's Sixth Amendment.
The Supreme Court does not often overrule a precedent, even if current justices question its reasoning, and especially when a new approach could disrupt legislatures and courts that have relied on it for years and built law around it.
Monday's first case concerned Allen Alleyne, who was convicted by a jury of robbery and firearms possession in the 2009 robbery of a convenience store in Richmond, Virginia.
Alleyne faced a minimum of five years in prison On the firearms charge, or seven years if a gun was brandished.
Jurors found Alleyne not guilty of brandishing a gun, on the grounds that there was reasonable doubt that he had. But the judge concluded otherwise, using the lower "preponderance of the evidence" standard of proof.
Alleyne's lawyer Mary Maguire argued that making - as the Harris case did - the brandishing a firearm a sentencing issue for the judge was unfair to defendants.
"You are stripping the defendant of the full benefit of the full jury verdict," she said.
Maguire faced sharp questions from the justices in response to her argument that Harris, a 5-4 decision, could be overturned in part because only a plurality of four justices agreed with all its reasoning.
"The doctrine can't be: 'We will overrule decisions that we don't like, but we will stick with decisions that the majority does like,'" Justice Samuel Alito said.
Recent decisions that have made jurors the fact-finders in criminal cases, and which have cut across the court's usual ideological divides, had their origin in a watershed 2000 decision - Apprendi v. New Jersey - requiring juries to find facts to raise a sentence beyond a prescribed maximum.
Lawyers for the government said abandoning Harris would disrupt courts that have relied on it, and state legislatures that have since passed laws governing mandatory minimums.
There is no "right to the mercy of a tender-hearted judge," said Michael Dreeben, a U.S. Department of Justice lawyer. "The 6th Amendment protects a right to a jury trial. It does not protect a right to judicial leniency."
The decisive vote could come from Justice Stephen Breyer, who dissented in Apprendi but later suggested he might have to accept it as it had been on the books for so long.
He appeared torn over the logic of failing to apply Apprendi to mandatory minimums as well as maximums.
"In the one case (a judge's) discretion is cut off to give a lower sentence; in the other case, his discretion is granted to give a higher sentence," Breyer told Dreeben.
"I see tremendous similarities, though I grant you the words are different."
Breyer is one of three justices in the Harris majority who remains on the court, but he did not accept all the reasoning of the other four justices in that majority, saying that the facts underlying the Apprendi and Harris cases could not be easily distinguished.
Monday's second case considered whether a state's failure for five years to pay for a lawyer for a defendant facing capital murder charges should lead to the indictment being thrown out on the grounds that he was denied a speedy trial.
Jonathan Boyer was indicted in 2002 for murder in Louisiana, which like many U.S. states requires a defendant in a death penalty prosecution to have two lawyers.
Money for a second lawyer was not found, and Hurricane Katrina in 2005 caused more delays. The death penalty was later taken off the table, but Boyer languished in jail for seven years before finally being convicted of second-degree murder.
Boyer's lawyers argued that Louisiana waited too long to try him, while Louisiana argued that the defendant and his lawyers were to blame for the delay.
The justices appeared split. Justice Ruth Bader Ginsburg expressed sympathy for Boyer, who according to his lawyers had a limited education and low IQ. "Did anyone ever tell this man with an eighth-grade education what his rights were?" she asked.
Scalia was less forgiving. "I am skeptical that a capital defendant who has confessed to a crime wants to be tried as quickly as possible," he said.
The case are Alleyne v. U.S., U.S. Supreme Court, No. 11-9335; and Boyer v Louisiana, U.S. Supreme Court, No. 11-9953.
Editing by Howard Goller and David Brunnstrom