HOUSTON (AP) A federal appeals court has rejected an East Texas inmate's claims that he's mentally impaired and ineligible for execution.

The 5th U.S. Circuit Court of Appeals had ordered another look at IQ scores for convicted killer Rickey Lynn Lewis.

The trial court, a federal district court and now the 5th Circuit, in a ruling late Tuesday, agreed the inmate's intellectual functioning is not "sub-average."

Courts generally have agreed an IQ of 70 is the threshold for mental impairment. Test results on Lewis range from 59 to 79 and his attorneys contend the higher scores are invalid.

The 50-year-old Lewis has been on death row since 1994, four years after George Ray Newman was fatally shot during a burglary of his home near Tyler. Evidence showed Newman's fiancee was raped.