HOUSTON (AP) — A 69-year-old prisoner on Texas death row for almost three decades for the slayings near Waco of three people — including the parents of his estranged wife — has lost a federal court appeal, moving him a step closer to execution.

Attorneys for Billie Wayne Coble contended testimony from a prosecution psychiatrist during his 2008 punishment retrial was unreliable and that a prison expert called by prosecutors gave fabricated testimony.

The 5th U.S. Circuit Court of Appeals ruled late Tuesday the psychiatrist's testimony wasn't unconstitutional and that a fabricated incident within the prison expert's testimony was harmless because it accounted for "only a small part" of the state's case against Coble.

Coble would turn 70 in September and is among the oldest of the state's 230 condemned inmates.

His lawyer, A. Richard Ellis, said Wednesday he hadn't yet decided whether to seek a rehearing before the appeals court "but either way I will petition for certiorari in the Supreme Court," meaning a review of the case by the justices.

In 2007, the 5th Circuit threw out Coble's original death sentence and ordered a new punishment trial. In that ruling, the court said two special issues that jurors had to answer to decide on the death penalty — whether Coble committed murder deliberately and would be a future danger to society — were unconstitutional as they were applied in his case.

The ruling then reflected changes in Texas statutes made since Coble's original trial in 1990, a year after he was charged with the shooting deaths of his estranged wife's parents, Robert and Zelda Vicha, and his wife's brother, Waco police Sgt. Bobby Vicha, at their homes in Axtell, northeast of Waco.

Evidence showed Coble was distraught over the breakup of his marriage, killed his wife's parents and brother Aug. 29, 1989, tied up several children from the Vicha family and then abducted his wife and drove off, assaulting her and threatening to rape and kill her. He was arrested after wrecking in neighboring Bosque County to end a police chase.