Scores of unexpected people are urging Missouri's governor to grant clemency to a death row inmate who's scheduled for execution on Tuesday — as his lawyers mounted a last-ditch effort Sunday to have the U.S. Supreme Court intervene.

Brian Dorsey's supporters include 72 current and former correction officers, five jurors who helped convict him and a retired Missouri Supreme Court judge who previously voted to uphold his death sentence, according to TV station KOMU.

Dorsey, 52, is set to receive a lethal injection at the state prison in Bonne Terre for murdering his cousin, Sarah Bonnie, and her husband, Ben Bonnie, on Dec. 23, 2006.

The slayings took place after the Bonnies took Dorsey into their home near New Bloomfield because he told them two drug dealers were at his apartment to collect a debt.

That night, he stole the couple's shotgun and killed them in their bed. The couple's 4-year-old daughter was home at the time but wasn't hurt.

Dorsey pleaded guilty and was sentenced to death in 2008, but he later argued he should have been sentenced to life in prison without parole.

In court papers, Dorsey has claimed he was incapable of premeditated murder because he was suffering from drug-induced psychosis after three days without sleep while withdrawing from crack cocaine.

His lawyers also maintain he didn't receive a proper defense because his attorneys at the time each received a flat fee of $12,000 from the Missouri State Public Defender system, which no longer pays flat fees in capital cases.

The Missouri Supreme Court twice upheld Dorsey's death sentence, in 2010 and 2014, and last month unanimously declined to stop his execution, with Judge W. Brent Powell writing that Dorsey "has not demonstrated he is actually innocent," according to the Associated Press.

The Missouri Supreme Court denied another motion for a stay of execution on Friday, KOMU said.

In a January letter to Gov. Mike Parson, the current and former correction officers described Dorsey as model inmate who deserved to have his sentence reduced to life without parole.

"Generally, we believe in the use of capital punishment," they wrote. "But we are in agreement that the death penalty is not the appropriate punishment for Brian Dorsey."

The five former jurors also asked for Dorsey's sentence to be commuted and former Supreme Court Judge Michael Wolff wrote that his decision to uphold Dorsey's death sentence was one of the "rare cases where those of us who sit in judgment of a man convicted of capital murder got it wrong."

Parsons will announce his decision on the clemency requests Monday, a spokesperson told KOMU.

Meanwhile, Dorsey's lawyers filed a petition with the U.S. Supreme Court on Sunday, saying that Dorsey was fully rehabilitated and that his execution would violate the Eighth Amendment because it would serve no legitimate form of justice, according to KOMU.