(CNS)—  An Aug. 4 preliminary hearing date was set Tuesday for a registered sex offender charged with the rape-murder of a Poway High School senior who vanished while running behind Rancho Bernardo Community Park.

John Albert Gardner III, 30, could face the death penalty if convicted of murder and a special circumstance allegation of murder during the commission of a rape or attempted rape.

District Attorney Bonnie Dumanis will decide after the August hearing whether Gardner will face the death penalty or life in prison without the possibility of parole if he’s convicted of killing Chelsea King.

Gardner was arrested Feb. 28 in connection with the 17-year-old cross- country runner’s disappearance three days earlier. Her body was discovered March 2 in a shallow grave in a tributary of nearby Lake Hodges.

Gardner is also charged with attempted assault on a Colorado woman who was running alone in Rancho Bernardo Community Park last Dec. 27.

According to Escondido police, Gardner is also the focus of an investigation into the disappearance and murder of 14-year-old Amber Dubois, who went missing 13 months ago. Her skeletal remains were discovered in a remote area of Pala on Saturday.

At  Tuesday’s hearing, Judge David Danielsen signed a protective order barring attorneys and police involved with Gardner’s case from releasing any information to the news media.