MEMPHIS, Tenn. — A death row inmate convicted of killing his wife more than three decades ago has opted not to choose his last meal after the governor decided not to intervene in his execution.

Donnie Johnson was sentenced to death for the 1984 murder of his wife, Connie Johnson, in Memphis. Investigators said he suffocated her by stuffing a 30-gallon trash bag down her throat and left her body outside the Mall of Memphis two weeks before Christmas.

He is scheduled to be executed by lethal injection on Thursday at 8 p.m. at Riverbend Maximum Security Institution in Nashville.

On Wednesday, the TN Department of Correction said Johnson opted not to choose a last meal, so he will be offered the same menu that is served to the rest of the prison population.

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He also wrote a letter to his family and his victim's family. He called himself a monster before accepting the Christian faith. He also asked for forgiveness in the letter. 

Johnson remains on death watch, which is the three-day period before an execution when the inmate is moved to a cell adjacent to the execution chamber where he is under constant 24-hour a day observation.

The U.S. Supreme Court declined this week to consider a challenge from Tennessee death row inmates who say lethal injection is cruel and unusual punishment. 

Johnson said he will not file any more legal challenges on Monday. Instead he asked for mercy from the Governor, with a request that his sentence be commuted to life without parole.

Governor Bill Lee decided Tuesday to deny that plea and will uphold Johnson's execution sentence.

"After a prayerful and deliberate consideration of Don Johnson‘s request for clemency, and after a thorough review of the case, I am upholding the sentence of the State of Tennessee and will not be intervening,” Lee said in a statement.

Attorney Robert Hutton has extensive experience with death penalty cases.

“The Governor always has power to commute any particular sentence and has very broad clemency powers,” Hutton said.

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Hutton says the governor had several factors to consider. One being that the jury at the time of Johnson’s sentencing did not have the option of life without parole because it was not a choice in the early 1980′s.

“You find many people end up voting for death, not because they think the person deserves to die, but because they are afraid they’ll be released from prison. We know in modern sentencing when juries have the option of life without parole the number of capital convictions goes way down,” he said.

Hutton also says that Governor Lee could also have considered that Connie Johnson’s daughter does not want her stepfather executed, and Johnson has been a model prisoner, becoming a Christian and helping other prisoners convert to Christianity.

Hutton says in the past governors have said several days before a scheduled execution what their decision is.

If and when Johnson is executed, he will be the fourth condemned man to die in Tennessee since August, when the state began executing inmates at a steady clip. The first was Billy Ray Irick, who murdered a 7-year-old girl in Knoxville.

Executions in Tennessee 

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