The attorneys representing death row inmates often have limited options by the time their clients are scheduled for lethal injection. Usually, the arguments with the best chances of saving an inmate’s life have already been heard and rejected by judges. Such is the case for Moises Mendoza, who the state plans to kill on April 23.
Mendoza stood trial in 2005 for killing Rachelle Tolleson in Farmersville, northeast of Dallas. It was an open-and-shut case. Mendoza confessed to the murder after being arrested. The only question was what his punishment would be.
To try to save him from the death penalty, Mendoza’s trial attorneys called an expert witness, psychologist Mark Vigen. Vigen’s job as he testified on Mendoza’s behalf was to humanize him, to help explain why he acted as he did and demonstrate that there were things in his life which mitigated his responsibility for the crime (common mitigating factors are mental illness or a history of physical or emotional abuse). But instead, according to a pair of appeals filed by Mendoza’s current attorneys, Vigen testified that nothing explained Mendoza’s actions, and that he remained dangerous.
“The first opinion that defense counsel elicited from Vigen dehumanized Mendoza completely,” his attorneys wrote in 2023. “Vigen told the jury that Mendoza lacks ‘the internal compass that each of us has’ and that he ‘has no … inner self’ and ‘no clear inner identity.’”
Vigen went on to testify that Mendoza chose “a depraved and disrespectful, aggressive, and drug-and-alcohol lifestyle in which … empty sexuality was involved.” As his attorneys wrote, “It is difficult to comprehend how an opinion characterizing a defendant’s life as ‘depraved’ could ever be helpful in a capital case.”
Vigen also agreed with prosecutors that Mendoza was very dangerous. During closing arguments, they reminded jurors of Vigen’s words. The jury gave Mendoza death. The defense’s witness had helped prove that he deserved to die.
“I rushed out of my cell and attacked Mendoza. He immediately fell to the ground and covered up to protect himself. He never threw a punch.” – Melvin Johnson, who fought Mendoza while incarcerated
In the appeals that followed, new attorneys argued that Mendoza’s defense team had violated his constitutional right to a fair trial by providing a substandard defense. A string of courts rejected the claim but Mendoza’s current attorneys revived it in 2023 and are making the argument again. They’re buttressing it with a new claim – that prosecutors presented false testimony during the sentencing phase of Mendoza’s trial, testimony that his trial attorneys failed to investigate and refute.
The alleged false testimony came from corrections officer Robert Hinton, who claimed that Mendoza attacked another inmate, Melvin Johnson, while in jail awaiting trial. Mendoza’s current attorneys have collected two separate accounts of the fight from Johnson, stating that he was the aggressor.
In the most recent of these accounts, collected last month, Johnson said he attacked Mendoza to please guards at the jail. “As I saw him walking down the stairs, my cell door opened,” Johnson told the attorneys. “I was shocked because a guard has to open my door and I was not supposed to be out with Mendoza. When my door opened with Mendoza out, I knew the guards wanted me to jump him, and that’s what I did. I rushed out of my cell and attacked Mendoza. He immediately fell to the ground and covered up to protect himself. He never threw a punch.”
Prosecutors used Hinton’s account of the fight – that Mendoza launched an unprovoked attack – to help secure his death sentence, saying it proved he would always be dangerous, even in prison. Johnson told Mendoza’s attorneys he was rewarded for starting the fight with an extra tray of food that night.
This article appears in April 18 • 2025.
