WASHINGTON (AP) — The Supreme Court ruled Tuesday that lower courts should take another look at an appeal from a Missouri man on death row for killing a woman and her two children 16 years ago.

The justices said inmate Mark Christeson should get a chance to argue that his court-appointed attorneys were ineffective because they missed a 2005 deadline to appeal his conviction in federal court.

It is uncommon for someone to be executed without a federal appeals court hearing.

Christeson would have been the 11th man executed in Missouri last year. But the Supreme Court put his execution on hold in October while it considered his appeal.

A group of attorneys argued that Christeson's court-appointed lawyers, Phil Horwitz and Eric Butts, should be replaced due to a conflict of interest because they would not admit their own ineffectiveness. The outside attorneys who reviewed the case file said substituting lawyers could give Christeston another chance to win federal review.

Horwitz and Butts missed the 2005 deadline to file a federal appeals petition by four months. But they declined to let outside counsel review documents that might show possible negligence in missing the deadline.

Last year, a federal court declined to substitute Christeson's lawyers. The 8th U.S. Circuit Court of Appeals also refused the request, prompting the appeal to the Supreme Court.

In an unsigned opinion, the Supreme Court said lower courts should have acknowledged that Horwitz and Butts faced a conflict of interest. The justices said the lawyers could not be expected to make a legal argument "which threatens their professional reputation and livelihood."

Justices Samuel Alito and Clarence Thomas dissented, saying they would not have reversed the appeals court's decision without full briefing and arguments from the parties.

Christeson faces death for killing Susan Brouk, 36, and her children in 1998. According to court records, Christeson, then 18, and his 17-year-old cousin, Jesse Carter, had planned to run away from a home outside Vichy in central Missouri where they were living with a relative. They walked a half-mile away to Brouk's home to steal her Ford Bronco.

Armed with shotguns, they tied her daughter and son's hands with shoelaces. Christeson forced Brouk into a bedroom and raped her. The pair then forced Brouk and the children into her Bronco and drove to a pond.

Brouk and Kyle were stabbed and thrown into the pond to drown. Adrian suffocated when Christeson pressed on her throat while Carter held her.