The Supreme Court's ruling came after prosecutors with the Harris County District Attorney's Office agreed with Bobby James Moore's attorneys that he should be spared the death penalty. The Texas Attorney General's Office had asked to take over the case in an effort to carry out the execution.
"The Harris County District Attorney's Office disagreed with our state's highest court and the attorney general to stand for justice in this case. The U.S. Supreme Court agreed. Bobby Moore is intellectually disabled," District Attorney Kim Ogg said in a statement.
Cliff Sloan, Moore's attorney, said he was "very pleased that justice will be done." Moore fatally shot 72-year-old Houston grocery store clerk James McCarble in 1980 during a robbery. He has been on death row for nearly 39 years.
This was the second time Moore's case had come before the high court. In 2017, the Supreme Court said the Texas Court of Criminal Appeals had used outdated standards to decide that Moore was not intellectually disabled. The case went back to the Texas appeals court, which in June again ruled Moore was not mentally disabled.
The Supreme Court in 2002 barred execution of mentally disabled people but has given states some discretion to decide how to determine intellectual disability. However, justices have wrestled with how much discretion to allow.
Texas looks at three main points to define intellectual disability: IQ scores, with 70 generally considered a threshold; an inmate's ability to interact with others and care for himself or herself; and whether evidence of deficiencies in either of those areas occurred before age 18.
In 2004, the Texas appeals court created additional factors, including whether an individual's conduct showed leadership and whether a person could "hide facts or lie effectively." In Tuesday's 6-3 ruling in the Moore case, the Supreme Court criticized the Texas appeals court for continuing to rely on the additional factors it had created.
The high court has said these factors, named after a former death row inmate named Jose Briseno, have no grounding in prevailing medical practice and invite lay stereotypes to guide assessment of such disability.
The Supreme Court said the Texas appeals court did not discuss evidence that seemed to support Moore's claims of intellectual disability, including that when he was in school, Moore was made to draw pictures when other kids were reading and that by sixth grade, he struggled to read at a second-grade level
In a concurring opinion, Chief Justice John Roberts — who had previously sided against Moore — joined the majority, saying the Texas appeals court "repeated the same errors that this Court previously condemned."
Moore's case is expected to be remanded back to a judge in Houston, who will resentence him to life in prison. While the change in his sentence means Moore would be eligible for parole, prosecutors say it's highly unlikely he will be released.
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