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Summary Article: Columbine High School Massacre
from Encyclopedia of School Crime and Violence

On April 20, 1999, what is considered one of the worst school shootings in U.S. history occurred at Columbine High School in Jefferson County, Colorado. In this attack, Eric Harris and Dylan Klebold—both students at the school—killed 12 students and a teacher, and injured 23 others, before killing themselves. The Columbine massacre is considered the deadliest school shooting for a U.S. high school, but the fourth-deadliest attack for a school, after the killings at the Bath Consolidated School in 1927, Virginia Tech in 2007, and the University of Texas in 1966.

Eric Harris and Dylan Klebold both had what seemed to be good, stable families. Klebold was going to go to college in the fall, although Harris had been turned down by a few colleges. Many have debated the causes of the shooting. It has been suggested that Klebold and Harris faced a great deal of bullying in a school that did little about the situation, causing them to become more isolated, angry, and violent. Other students admitted that they teased Klebold and Harris endlessly. They claimed that no one liked the pair, and that they teased them because Klebold and Harris seemed weird (as if they were gay). According to some sources, everyone made fun of the duo to get rid of them or make them act more normal. In the video Harris and Klebold made before the shooting, they said they planned to get back at everyone for the harassment they had faced for so long. Many believed Harris and Klebold planned to get even for their inability to gain acceptance for many different cliques. They plotted against popular people, students who had made fun of them, and students who ignored them.

Columbine High School offers a message of hope on a sign after the infamous shootings at the school.

(Bambi L. Dingman/

Klebold and Harris played violent video games such as Doom, and some suggest that the pair had become desensitized toward violence through these games, as well as through violent music and movies. Five years after the shooting, a number of psychiatrists and the FBI's main Columbine investigator publicly stated that they believed Klebold had depression and Harris was a clinical psychopath who had control over Klebold. According to these investigators, a major factor in the shooting was that Harris needed to feel he was superior over others. Later, other psychiatrists weighed in against these opinions, suggesting that the diagnoses were not accurate. Critics held that the violent video games Klebold and Harris played, instead of aggravating their anger, helped them release their aggression. According to this view, when the youths were not allowed to play video games as frequently as a form of punishment, they had to instead get their aggression out in the real world.

The school shooting was not the first time Klebold and Harris had gotten in trouble. On January 30, 1998, both were arrested for stealing tools from a van. They had to take classes and meet with parole officers. Harris also had to go into therapy, which he attended for approximately a year. Both got out of the program early for good behavior. Harris even wrote a letter of apology to the van's owner, and then wrote in his journal later about how he faked it. Harris was also making plans with Klebold to attack the school even while he was in therapy. He was put on Zoloft (an antidepressant) while in therapy, but told the therapist that the medication was giving him suicidal thoughts as well as urges to harm others. The doctor switched him to Luvox, another antidepressant. It was discovered that Harris had this drug in his system when he died. Although these drugs were intended to help Harris, some psychiatrists believe they may have actually led to his violent urges, as these agents have been known to cause depersonalization and increased aggression.

After the attack, officials found journals and videos documenting the plans made by Klebold and Harris. Klebold and Harris had originally planned to bomb the school, shoot any survivors, and then start shooting neighbors and others who came to see what was happening. Harris had created a website that included basics on making bombs and how to cause trouble; the site also documented the mischief he and Klebold had been getting into. It was discovered later that an Investigator with the Jefferson County Sheriff's Office knew about Harris’ website two years before the school shooting occurred. The investigator, Michael Guerra, started looking into the website after the parents of another student, Brooks Brown, complained that the site contained threats against their son. Guerra also found threats against many other people at Columbine High School on the site as well as blogs about how Harris hated society. Harris even had a “hit list” on the site, and a list of the guns and bombs he had. Guerra had intended to obtain a search warrant for Harris's home, but never did—it was later discovered that there was not probable cause to obtain one. Members of the Sheriff's Office and other high-ranking officials of the county decided not to mention they had knowledge of this website at the time of the shooting. The documents that stemmed from this knowledge were lost over time, and the officials’ previous access to Harris's website was not disclosed until September 24, 2001.

For the shooting, Klebold and Harris bought a rifle and two shotguns from a friend who had purchased the weapons at a gun show. They also collected two 12-gauge shotguns and two 9-mm firearms. They used the Internet to learn how to build their bombs, eventually constructing 99 of them.

On April 20, before they went to the school, Klebold and Harris set a fire bomb in a field near the school to go off at 11:14 a.m. (Mountain Daylight Time). Police speculate that this event was intended to distract emergency vehicles and keep them away from the school. Klebold and Harris arrived at the school at 11:10 a.m. and parked outside the cafeteria. They brought two propane bombs hidden in duffel bags into the cafeteria during the first lunch shift, and left the bags on the floor amidst an array of other students’ bags. These bombs were set to go off at 11:17 a.m. After they put the bags down, Klebold and Harris went to their cars to wait for the bombs to explode, planning to shoot students as they ran from the cafeteria.

When the bombs did not go off in the cafeteria, Klebold and Harris had to make an alternate plan. They took their guns and started shooting students who were outside the school, eating lunch and on the staircase outside. They then shot at students in the soccer fields and threw pipe bombs, although none of the shots made their mark and the bombs did not go off. A teacher, Patti Nielson, went to see what was going on and was hit by shrapnel in the shoulder from shots from Harris and Klebold. She ran to the library to warn students to be careful; from there, she called the police. The sheriff arrived at about 11:24 a.m., and shot at Klebold and Harris. Harris shot back and the sheriff made a call for backup.

At that point, Harris and Klebold ran through the school, shooting at anyone who was there and throwing more pipe bombs. The two shooters then made their way to the library, which was considered the worst part of the shooting that day. First they threw two bombs into the cafeteria and one in the library hallway; this time, all of the bombs did explode. Klebold and Harris entered the library at 11:29 a.m., where two teachers, two librarians, and 52 students were taking refuge. Harris and Klebold started yelling at everyone who was hiding to stand up. No one obeyed the command, so the two started shooting anyway. They killed one student, but then saw police evacuating students outside. The pair shot at the police through the windows, and the police shot back. However, the shooters’ attention quickly turned back to the students inside the library. They started shooting under computer desks, where students were hiding, injuring and killing more students. Klebold and Harris also walked around the library, knocking down shelves and shooting more students, as well as throwing more bombs.

According to witnesses, Klebold and Harris starting talking to each other about how the shooting was no longer exciting to them. They thought of possibly attacking people with knives, which they supposed might be more fun. Instead of doing so, however, the pair left the library at 11:42 a.m. As soon as they left, some students fled the library and managed to get outside the building, while others hid in the staff break room until about 3:30 p.m.,when police found them.

Meanwhile, Klebold and Harris wandered through the school, shooting and throwing bombs as they went. At 12:02 p.m., they went back into the library, which was now empty except for unconscious students on the floor. This is where, at the end of it all, Harris and Klebold killed themselves. Eric Harris, age 18, shot himself in the mouth one time. Dylan Klebold, age17, died from a single shot to his head.

At 1:09 p.m., the SWAT team went into the school, after the shootings had ended. Team members determined that the school was safe at 4:30 p.m., but later found more explosives, including in Klebold's car; thus the school was not officially declared safe to enter again until 10:00 a.m. the next day. Officials believe the shootings lasted for 45 minutes before Klebold and Harris shot themselves. In total, they killed 12 students and one teacher, and injured 24 others; another three people were injured trying to get out of the school. The casualties of the shooting that day were Cassie Bernall, Matt Kechter, Corey DePooter, Isaiah Schoels, Daniel Rohrbough, Steve Curnow, Lauren Townsend, Kelly Fleming, Kyle Velasquez, Daniel Mauser, John Tomlin, Rachel Scott, and Coach Dave Sanders.

Officials started their investigation at 11:30 a.m. on April 21, while 13 bodies were still in the school. The victims were not taken out of the school to be identified until the late afternoon and early evening that day. During the investigation, officials held a press conference to say they believed other people had helped plan the shooting.

Columbine differed from some school shootings in that afterward, there was no one to take to trial, as Harris and Klebold both killed themselves.

The shooting at Columbine High School opened American society's eyes to many issues related to youth and safety. People began more closely scrutinizing youth violence, gun control laws, high school subcultures, bullying, and the effect of media such as video games, after this shooting occurred. Harris and Klebold also influenced many other school shootings or attempted school shootings, as other students wanted to be like them or wanted to outdo them.

Further Reading
  • CNN. (2000, May). Report: 12 killed at Columbine in first 16 minutes. Retrieved December 12, 2008, from
  • Fine, M., Weis, L., Pruitt, L., & Burns, A. (2004). Off white: Readings on power, privilege, and resistance, 2nd ed. Routledge New York.
  • Jefferson County Sheriff's Office. (n.d.). The Columbine report. Retrieved December 14, 2008, from
  • The Rocky Mountain News. (n.d.). Columbine High School shootings. Retrieved December 14, 2008, from
  • Thiel, Sharon
    Copyright 2011 by Laura L. Finley

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