Updated

Attorneys for a man convicted of stabbing a Texas corrections officer to death over a disagreement about a peanut butter sandwich are asking the U.S. Supreme Court to block his execution.

Thirty-five-year-old Robert Pruett is scheduled for lethal injection Tuesday evening in Huntsville for killing Daniel Nagle in 1999.

The 37-year-old officer was working at the McConnell Unit about 85 miles southeast of San Antonio where Pruett was serving a 99-year sentence for his role in a Houston-area killing.

Evidence at Pruett's trial showed he was upset Nagle had written a disciplinary report after the prisoner tried to take a peanut butter sandwich into a recreation yard in violation of rules. Pruett's lawyers insist he's innocent and that another inmate or corrupt prison guards were responsible for Nagle's death.