ATLANTA (AP) — A Georgia man convicted of forging checks and killing a close friend of his mother is to be executed Tuesday despite his claims that he didn't commit the murder.

Brian Keith Terrell, 47, is scheduled to die at 7 p.m. at the state prison in Jackson. He was convicted in the June 1992 killing of John Watson in Covington, about 35 miles east of Atlanta.

Terrell's lawyers say their client is innocent, that no physical evidence connects him to the crime and prosecutors used false and misleading testimony to get the conviction. State lawyers say courts have already heard and rejected the defense arguments.

The Georgia Board of Pardons and Paroles, which is the only entity with the authority to commute a death sentence, on Monday denied Terrell's request for clemency. He filed appeals Tuesday after state and federal courts rejected his challenges.

Terrell was on parole when he stole and forged checks belonging to Watson, who reported the theft but asked police not to pursue charges if Terrell returned most of the money. On the day Terrell was to return the money, he had his cousin drive him to Watson's house, where he shot the 70-year-old man several times and severely beat him, lawyers for the state have said.

Terrell's cousin, Jermaine Johnson, was his co-defendant and had been in jail for more than a year facing the possibility of the death penalty when he agreed to a deal with prosecutors to testify against Terrell. Johnson was allowed to plead guilty to a robbery charge, receiving a five-year prison sentence.

A defense investigator wrote in a sworn statement that Johnson told her and defense attorney Gerald King that he was 18 and facing the death penalty and was pressured by police and the prosecutor to testify against his cousin. He said he'd like to give a sworn statement telling the truth but is afraid he might be arrested and put in prison for perjury if he does, Goodwill wrote.

Prosecutors also misleadingly presented the testimony of a neighbor of Watson's, incorrectly asserting that she said she saw Terrell at the scene, Terrell's lawyers wrote.

Terrell's arguments have already been reviewed and rejected by courts, state lawyers argue.

A state court on Thursday dismissed the complaint in which Terrell claimed innocence, and he has appealed to the state Supreme Court.

Terrell has also filed a court challenge saying the state cannot ensure the safety or efficacy of the drug it plans to use to execute him. A federal court on Thursday rejected that challenge, and Terrell appealed to the 11th U.S. Court of Appeals.

Terrell was previously set for execution on March 10. But after Department of Corrections officials discovered solid chunks had formed in the drug that was to be used in the execution of Kelly Gissendaner on March 2, they temporarily suspended all executions to allow time for an analysis of the compounded pentobarbital.

The state has said that most likely cause for the precipitation in the drug was because it was shipped and stored at a temperature that was too cold. The state has taken precautions to prevent that from happening again and would not proceed with an execution if a problem with the drug was discovered, state lawyers have said.

Gissendaner was executed Sept. 30 and another inmate, Marcus Ray Johnson, was executed Nov. 19.