AUSTIN, Texas — On Wednesday evening at the Texas State Penitentiary at Huntsville, Willie Trottie, 45, was executed by lethal injection after he unsuccessfully tried to petition the United States Supreme Court in an appeal that challenged the drugs used by Texas to carry out lethal injections. Trottie’s execution was the eighth in Texas so far this year.

Trottie had been convicted of murder in connection with the May 1993 deaths of his estranged common-law wife, Barbara Canada, 24, and her brother, Titus Canada, 28, at their parents’ home in Houston. He had admitted shooting the victims but had contended that it was accidental and in self-defense. Prosecutors had countered that Trottie had threatened to kill Ms. Canada if she left him, and that she had obtained a protective order against him. Trottie shot Ms. Canada eleven times, and her brother twice in the back of the head.

Recent executions in Oklahoma, Ohio, and Arizona drew headlines when the process encountered difficulties and possibly prolonged the suffering of the condemned inmates. However, Trottie’s execution  was without such problems, according to The Dallas Morning News, which reported that Trottie “closed his eyes and breathed quietly” as the pentobarbital took effect, and then “[a]fter about eight breaths, he opened his mouth to exhale, then closed it. There was no further movement.” Trottie was pronounced dead at 6:35 p.m. CDT. The entire process took 22 minutes from the administering of the drug to Trottie’s death.

A major part of Trottie’s appeals had focused on a challenge to the drug used by Texas for lethal injections. Earlier this year, Texas Attorney General Greg Abbott had reversed previous policy and instructed the Texas Department of Criminal Justice (TDCJ) to “withhold the identifying information of the pharmacy and pharmacist” responsible for synthesizing the drug used. TDCJ officials had argued that because of the highly politicized and controversial nature of executions, any pharmacy engaged in supplying the needed drugs would be under “substantial threat of physical harm.”

Trottie’s attorneys challenged that decision to keep the pharmacy’s identity confidential, and also argued that the drugs intended for his execution were expired, and this presented a “substantial risk that this execution will inflict severe and tortuous pain,” in violation of the Eighth Amendment’s prohibition on cruel and unusual punishments. The Texas Tribune reported that a spokesman for the TDCJ had said that the pentobarbital dose designated for Trottie’s execution had a “by use date” of September 30, and a back up dose they had set aside had a “by use date” of October 31.

The Supreme Court denied Trottie’s request to hear his appeal and also denied his request for a stay of execution and his execution was carried out about ninety minutes later. Before his execution, Trottie repeatedly asked for forgiveness from witnesses, including relatives of his victims. “I love you all,” he said. “I’m going home, going to be with the Lord…find it in your hearts to forgive me. I’m sorry. Stay strong. Jesus take me home. “

Follow Sarah Rumpf on Twitter at @rumpfshaker.