An 18-year-old man who was allegedly racing a friend when the 16-year-old boy crashed his car on state Route 52, killing two passengers, must stand trial on felony charges, including vehicular manslaughter while intoxicated, a judge ruled Thursday.Michael Sebastian Johnson, a graduate of Santana High School, faces 15 years in state prison if convicted of two counts of gross vehicular manslaughter and one count each of engaging in a speed contest resulting in injuries and reckless driving, along with possession of marijuana while driving, an infraction.Superior Court Judge Robert F. O'Neill ruled that enough evidence was presented during the defendant's preliminary hearing to order him to proceed to trial.Defense attorney Russell Babcock said he may a file a motion to dismiss the charges. A readiness conference was set for June 7.Deputy District Attorney Kristen Spieler said the defendant was racing and zigzagging in and out of traffic just before his friend's car crashed near Convoy Street on April 4 about 11:45 p.m. as they headed home from a bonfire at La Jolla Shores.Spieler said Johnson -- who stayed at the scene after the crash -- appeared to be under the influence, and a small amount of marijuana was found in his car.Six hours after the accident, Johnson showed symptoms of impairment and had a green substance on his tongue consistent with marijuana use, the prosecutor said. A lab report indicated Johnson had marijuana in his system, according to court testimony.But Babcock argued there was no evidence that Johnson smoked any marijuana the night of the accident, and he questioned whether his client could be held legally responsible for the victims' deaths."This was not a race," Babcock told the judge.The 16-year-old driver of the car that crashed was charged in Juvenile Court with vehicular manslaughter, but prosecutors seek to have him tried as an adult.California Highway Patrol Officer Art Athans said the younger suspect was behind the wheel of a Volkswagen Passat, taking four other teenagers home from the beach party, when he lost control of the sedan, which careened into a center divider near Convoy Street, struck a bridge pillar and flipped seven times, end over end.Two back-seat passengers in the Passat, 16-year-old Jayli Campbell and 18-year-old Anthony Foreman, were ejected from the vehicle and died at the scene. The other two passengers, a 17-year-old boy and a 15-year-old girl, were seriously injured.The teenage driver, who sustained moderate injuries, was found to have been sober at the time of the accident.Johnson, who was driving a Volvo S40 that did not crash, was not injured, nor were his two passengers.Babcock said the two drivers left the bonfire at different times, and Johnson claimed the other driver passed him at high speed just before crashing.But Spieler said other drivers on the freeway were forced to take defensive action, and one witness saw both cars pass by at 100 mph. Security officer Jeremy Benson said after the Passat sped by, "It hit a bump and the back tires had lifted up slid to the right and just went straight into the wall. It was airborne." When confronted by officers after the fatal crash, Johnson admitted racing the other driver, then later denied it, saying he was only going 75 mph, the prosecutor said. CHP Officer Mark Maldonado said in his initial questioning of Johnson, he asked if they'd been racing. "He said, 'Yes, we were.' and ducked his head," Maldonado said. Spieler asked, "What do you mean?" Maldonado responded, "Kind of remorseful when I asked him. He kind of ducked his head and said, 'Yes, we were.'"After a brief interruption, Maldonado said, "I came back to continue to interview Mr. Johnson, at which point he stated, 'I wasn't racing. I just got nervous when you asked me.'" Spieler said the 16-year-old called Johnson on a cellphone as they were racing, but Johnson didn't answer. O'Neill said the fact that Johnson changed his story indicates "a guilty mind."