HOUSTON (CBSDFW.COM/AP)A black Texas prison inmate who earlier this year won a U.S. Supreme Court order for a new punishment hearing because his death sentence may have been tainted by references to race has accepted a life prison term plus two 60-year sentences.

“After reviewing the evidence and the law, I have concluded that, 22 years after his conviction, a Harris County jury would likely not return another death penalty conviction in a case that has forever been tainted by the indelible specter of race,” Harris County District Attorney Kim Ogg said Tuesday.

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In return for 54-year-old Duane Buck pleading guilty to two additional counts of attempted murder, Ogg said her office won’t pursue the death penalty against him.

Buck’s attorneys had tried for years to get federal courts to look into claims that his rights were violated when a psychologist at Buck’s 1997 capital murder trial, Dr. Walter Quijano, said “yes” when asked whether Buck is more likely to be dangerous because he is black.

VIDEO: “A Broken Promise in Texas: Race, the Death Penalty and the Duane Black Case.”

In Texas death penalty trials, one of the “special issues” jurors must consider when deciding punishment is whether the defendant they’ve convicted would be a future danger.

The high court, in a 6-2 ruling in February, said the race reference in testimony was improper.

“Our law punishes people for what they do, not who they are. Dispensing punishment on the basis of an immutable characteristic flatly contravenes this guiding principle,” Chief Justice John Roberts said in his majority opinion.

Roberts wrote that the testimony of Dr. Walter Quijano “was potent evidence. Dr. Quijano’s testimony appealed to a powerful racial stereotype — that of black men as ‘violence prone.”

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Buck was convicted of killing his ex-girlfriend and another man in 1995. His case was among six in 2000 that then-Texas Attorney General John Cornyn, now the state’s senior U.S. senator, said in a news release needed to be reopened because Quijano’s statements were racially charged. In the other five cases, new punishment hearings were held and each convict again was sentenced to death.

Buck’s lawyers contended the attorney general, by then Cornyn’s successor and now Texas Gov. Greg Abbott, broke a promise by contesting his case. But the 5th U.S. Circuit Court of Appeals said it could find nothing in the case record to indicate the state made an error or promised not to oppose any move to reopen the case.

One difference in Buck’s case is that Buck’s own lawyer, not the prosecutor, elicited Quijano’s testimony. State attorneys said the difference was reason enough to rule against Buck.

Roberts, however, said when race is a factor in jury deliberations, it doesn’t matter “which party first broached the subject.”

Buck was convicted of murdering Debra Gardner and Kenneth Butler and he pleaded guilty Tuesday to attempting to murder Phyllis Taylor and Harold Ebenezer during a July, 30, 1995 attack at Gardner’s home. The 60-year terms for attempted murder are to run concurrent with the life sentence for capital murder.

Ogg said the facts of Buck’s crimes were not in dispute.

“However, this case can accomplish something,” she said. “It can close a chapter in the history of our courts, in that they will never again hear that race is relevant to criminal justice or to the determination of whether a man will live or die. Race is not and never has been evidence.”

Buck will be eligible for parole in 2035. Ogg said her office would oppose any parole.

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