The Colorado Supreme Court has upheld a trial court ruling overturning the first-degree murder conviction of David Bueno (pictured) after Arapahoe County prosecutors who sought the death penalty against him in a prison killing hid evidence that pointed to another suspect. The January 22 ruling comes in the wake of a trial court ruling that prosecutors in the state’s 18th Judicial District, which includes Arapahoe County, also suppressed more than twenty pieces of evidence that should have been disclosed to the defense in the capital trials of death-row prisoners Sir Mario Owens and Robert Ray.

Bueno’s lawyer, David Lane, called the pattern of prosecutorial conduct in the 18th Judicial District, “Mississippi in the mountains.” “Ethically, prosecutors are required to seek justice, not convictions,” he said. “But they apparently lose sight of that on a regular basis, especially on death-penalty cases in the 18th Judicial District.”

Bueno and a second Latino prisoner, Alex Perez, were charged with stabbing a white prisoner, Jeffrey Heird, to death in 2004.

The day before the murder, another white prisoner, Michael Snyder, told his wife in a phone call recorded by the prison that he had been ordered to stab a prisoner. The evening after the murder, a prison nurse found a note containing threats by a white supremacist prison group to kill “men of the white race who refuse to accept their proud race.” The nurse immediately prepared an incident report that included a copy of the letter. One day later, another white inmate died under suspicious circumstances and a prison lieutenant who was investigating the death prepared a second report suggesting the deaths might be connected.

The court wrote that undisputed evidence established that “the prosecution possessed both of these reports within days of Heird’s murder but did not provide copies of them to Bueno until five years later,” after he had been convicted. Despite specific requests by the defense to be provided all incident reports, and in violation of its constitutional obligation to disclose all potentially exculpatory evidence, the court found prosecutors had made “a conscious decision … to keep the information from the Defendant.” The court agreed with the trial judge that these violations were prejudicial because “[t]he identity of Heird’s killer was the core issue at trial, with Bueno arguing that white supremacists had committed the murder,” and the jury had taken four days to deliberate, including asking the court how to overcome a deadlock. The jury then imposed a life sentence, rejecting the death penalty in the case.

In a 2010 interview with Westword after the trial court had overturned Bueno’s conviction, Lane called it “truly stunning that the prosecutors in this case hid evidence that was so favorable to the defense” and said “it is particularly shocking in light of the fact that this was a death penalty case.”

A 2015 study showed significant racial and geographic disparities in the prosecution of death-penalty cases in Colorado, with non-white defendants and defendants in the 18th Judicial District statistically more likely to be capitally prosecuted. All three prisoners on Colorado’s death row are from the 18th Judicial District. 18th District DA George Brauchler, who opposed the grant of a new trial in the case, is currently seeking election as Colorado’s Attorney General.

In a similar case from Texas, prisoner Robert Pruett was executed on October 12, 2017 for the murder of prison guard, Daniel Nagle. No physical evidence tied Pruett to the murder and, according to Pruett’s clemency petition, Officer Nagle had been working as a whistleblower to identify corrupt correctional officers who had been helping prison gangs launder drug money. Nagle’s name was discovered on a note from an inmate saying that a prison gang wanted him dead. DNA on the murder weapon did not match either Pruett or Nagle, and Pruett had argued that DNA belonged to the actual killer.