The U.S. Supreme Court has refused to review an appeal from condemned Texas inmate Duane Buck, whose supporters contend his death sentence decided by a Houston jury 17 years ago unfairly was based on race.

"His death sentence is the product of pervasive racial discrimination," attorneys Christina Swarns, Kathryn Kase and Kate Black said in a statement Wednesday.

Without comment, the high court Tuesday rejected Buck's appeal. The ruling was an appeal of a similar rejection in November from the Texas Court of Criminal Appeals, the state's highest criminal court.

Buck, 50, was convicted of capital murder and sent to death row for the slaying of his ex-girlfriend and a man at her Houston apartment in July 1995. During the punishment phase of Buck's 1997 trial, psychologist Walter Quijano testified under cross-examination by a Harris County prosecutor that black people were more likely to commit violence.

Advocates for Buck, who is black, say that unfairly influenced jurors, who in Texas capital cases must decide when deliberating a death sentence whether an offender would be a continuing threat. Quijano, called as a defense witness, had testified earlier that Buck's personality and the nature of his crime, committed during rage, indicated he would be less of a future danger.