IN MARCH 2001, TWO TEENS DIED IN A SCHOOL SHOOTING AT CALIFORNIA'S SANTANA HIGH SCHOOL. JOSH STEVENS MIGHT HAVE PREVENTED THE TRAGEDY, IF ONLY HE'D SPOKEN UP

In February 2001, I was walking home from school when my friend Andy Williams suddenly said, "I wanna pull a Columbine." He'd had a really bad day-a teacher had embarrassed him in front of the class-and I thought he was kidding. "All right, Andy," I joked.

Like me, Andy was a ninth-grader at Santana High School in Santee, Calif. We hung out at the local skatepark and got to be great friends. We both liked punk and heavy metal, and we both played bass guitar. Andy was hilarious, but looking back, I can see he struggled with depression. He'd moved to California from Maryland and was having a hard time fitting in because he wasn't tough like other kids in our neighborhood.

I dismissed Andy's "Columbine" comment until two days later when a bunch of us were just hanging out. From nowhere, Andy suddenly said he wanted to take a gun and shoot people in the school hallway. One girl made him promise he wouldn't. "OK, I promise," Andy said, smiling. But several days later, he asked me and another friend if we wanted to get guns and do "it" with him. We were like, "No! Are you serious?" He said he was kidding.

On Monday, March 5, 2001, just before 9:39 A.M., a friend banged on my bedroom window and yelled, "Andy did it!" I got dressed and ran the three blocks to school. The campus was total chaos: people running everywhere, police cars and ambulances with their lights flashing. Andy had taken his dad's .22-caliber revolver and randomly sprayed bullets in a bathroom and hallway. Thirteen people had been injured and two others had been killed.

The police questioned me for eight hours. Word spread that Andy had told me about his plans and [that] I'd done nothing to stop him. The school district refused to let me come back to school, and it suddenly seemed like every student was out to kick my butt. People even called me at home to threaten me. It got to the point where I just stayed home and slept all the time.

Nobody wants to be a rat, but you have to tell someone if one of your friends threatens violence. My best friend is in jail and two people lost their lives, and that will always hang over my head. In the weeks after, I started hanging out with a group of druggies-I think as a way to escape what had happened and how I might have prevent it. Before long, I was arrested for drug possession. The judge sentenced me to six months in a residential treatment center, where I am now. I honestly don't think any of this would have happened if not for the shooting.

I'll be here until February, and then I plan to finish school. I've also become a spokesperson for PAX, an organization that helps prevent gun violence. I don't want another school shooting to happen, and nobody should go through what I did. If I could do things over, I would have personally gone to Andy's house and told his father what was going on.

THE PAX PLAN: SPEAK UP

Students are in a position to prevent school shootings 75% of the time. To anonymously report threats of violence at your school, call PAX's toll-free tips hotline at 1-866-SPEAK-UP