HOUSTON — The U.S. Supreme Court has refused to review an appeal from a 35-year-old San Antonio man on death row for a fatal shooting during a robbery nearly 13 years ago.

The high court, without comment, ruled Monday in the case of Juan Castillo. Earlier this year, a lower federal appeals court turned down Castillo’s arguments that his trial legal help was deficient.

Castillo was convicted of the December 2003 slaying of 19-year-old Tommy Garcia Jr. Evidence showed Garcia was lured to a San Antonio lovers lane by Castillo’s girlfriend and then ambushed. She pleaded guilty before Castillo’s 2005 trial and testified against him.

Late in his trial, Castillo fired his lawyers and represented himself, cross-examined no witnesses during the trial’s punishment phase and made no final argument to jurors.