Suzi and Doug O'Brien were escorted Monday morning into the photography room in the Sonoma County morgue before a forensic assistant pulled on the zipper of a black body bag to reveal the bloodied and bruised face of their daughter, Mariah Pennewell.

"It was horrible," Suzi O'Brien said, dabbing her teary eyes. "I want to take her home."

O'Brien, who was still crying after she had left the morgue, said her emotions were real, despite knowing that the scene was part of the staging of "Every 15 Minutes," an elaborate, two-day production that re-enacts a deadly vehicle collision involving teens who were driving while drinking, using drugs or distracted.

The long-standing program is typically staged at area high schools once every four years so that all students on campus experience the crash scene, the obituaries being read aloud in class, the empty seat of classmates who never show up for school and the culminating school assembly during which a mock funeral is held and students view a video of the entire drama.

"Death notices" are delivered to the knowing parents of 31 students who never showed up for school Monday. Obituaries are read in class for every student involved — with the intent that every Rancho Cotate student will be affected by at least one person's "death."

On Monday, crews filmed the crash scene and emergency repose, followed parents into the morgue viewing room, into the Kaiser Permanente emergency room, county jail and later a courtroom, where Rancho Cotate senior Derek Hammonds was "arraigned" for DUI and causing the death of two of his classmates. The entire school will gather Tuesday to watch the video.

"It's so graphic and so real; we have to be very mindful of the emotions of everybody involved," said Rohnert Park Public Safety Department Sgt. Jeff Nicks, who coordinated the event with Rancho Cotate High School assistant principal Angie Scardina.

"Parents show up at the hospital; it's almost overwhelming," he said. "Even though you know it's fictional, you see your child there, you see doctors and nurses and tubes coming out of the child."

The program, funded in large part by a $10,000 grant from the California Office of Traffic Safety, brings together police and fire crews, CHP, school officials, Sonoma County Sheriff's Office, Sonoma County Superior Court, Kaiser Permanente and others to drive home the perils of driving while drinking or high, or while distracted by texting or talking on the phone.

Motor vehicle crashes are the leading cause of death for U.S. teens, according to the Centers for Disease Control and Prevention. Per mile driven, drivers ages 16 to 19 are three times more likely than drivers aged 20 and older to be in a fatal crash.

In 2010, seven teens ages 16 to 19 died every day in the U.S. from motor vehicle injuries.

In 2009, an estimated 6.3 percent of students ages 16 or 17 drove under the influence, according to the 2009 National Survey on Drug Use and Health. The rates steadily increased with age to a peak of 25 percent of those ages 21 to 25 saying they drove under the influence.

Hammond played the drunken driver in Monday's staged event, emerging from a wrecked sedan on the school track and walking with wobbly legs around the staged mess of tangled metal and fake blood.

Hammond, who performed and failed a field sobriety test given by Nicks just moments after a CHP helicopter landed on a nearby ball field, was put in handcuffs and carted away to jail.

"I think it's cool that they put it out there," he said of the larger message of the day.

The message has particular resonance for Hammond. His older sister was injured while riding in a car with a drunken driver nearly a decade ago, he said.

"My mom still talks about it," he said, gory makeup glued to his face.

The four students involved in the re-enactment, as well as 31 others who school officials consider leaders among their groups of friends, did not attend school Monday and participated in an overnight retreat.

Students were scheduled to listen to speakers affected by drunk driving, as well as emergency responders who have seen the aftermath of teen crashes. During the retreat students are asked to write letters to their parents with the premise "I wish I had the chance to tell you this .<TH>.<TH>."

Parents, who also met with officials and counselors Monday night to address how the program made them feel, are asked to write letters to their students.

"It's really heartfelt and pretty powerful," Nicks said.

Rancho Cotate junior Sergio Bobadilla said he worried about his parents' reaction, even though the delivery of death notices were staged.

His face painted white and wearing his "Every 15 Minutes" T-shirt, he tried to rub the chills off his arms while talking about it.

Pennewell's dad Doug O'Brien said the day's events were important to getting the message out to students about the perils of drinking and driving. But on Monday, the impact hit him as a parent just as hard.

"To see her where she could not talk to us or smile at me ever again?" he said. "No way."

News researcher Janet Balicki contributed to this report. Staff Writer Kerry Benefield can be reached at 526-8671, kerry.benefield@press democrat.com or on Twitter @benefield.