Texas set to execute man convicted of killing two in store robbery
Death row inmate Terry Darnell Edwards is seen in an undated picture released by the Texas Department of Criminal Justice. REUTERS/Texas Department of Criminal Justice/Handout via Reuters/File Photo

A Texas death row inmate has launched last-minute appeals to halt his Thursday execution, with lawyers for the man convicted of double murder saying he was not the trigger man and his case was tainted by prosecutorial misconduct and poor prior counsel.

Terry Edwards, 43, is set to be put to death by lethal injection at the state's death chamber in Huntsville at 6 p.m. If the execution goes ahead, it would be the 540th in Texas since the U.S. Supreme Court reinstated the death penalty in 1976, the most of any state.

He was convicted along with co-defendant Kirk Edwards, an older cousin, of the July 2002 murders of Dallas Subway sandwich shop employees Mickell Goodwin and Tommy Walker in a robbery.

Kirk Edwards has a projected release date of July 2027, Texas Department of Criminal Justice online records showed.

On Wednesday, the U.S. Court of Appeals for the Fifth Circuit denied an appeal to halt the execution. Lawyers for Edwards then filed a motion with the U.S. Supreme Court seeking to spare his life.

In an editorial posted online on Wednesday, the Dallas Morning News said the execution should be halted because there are too many unanswered questions in the case.

"These questions do not paint Terry Edwards as innocent. But they do raise uncertainties as to whether the jury was misled when it determined he had pulled the trigger and deserved to die, it said.

Lawyers for Texas have argued that new counsel for Edwards has previously tried to halt the execution on similar grounds and his execution should go ahead as a result of a conviction and sentencing that were legal and proper.

John Mills, an attorney for Edwards, said he has evidence indicating that Edwards was not the gunman.

"Previous counsel has done virtually almost nothing to ensure that his case was investigated and that the powerful evidence undermining the reliability and the fairness of his conviction was brought to light," Mills said in an interview.

One of the main pieces of evidence was gunshot residue testing, which at trial was presented and used by prosecutors who said Terry Edwards fired the fatal shots.

In court papers, lawyers for the death row inmate said the gunshot residue evidence was improperly interpreted and actually show that Edwards was not the shooter.

(Reporting by Jon Herskovitz; Editing by James Dalgleish)