Columbine High School shooting

The Columbine High School shooting on the morning of April 20, 1999, ultimately left 16 dead in a mass shooting in Littleton, Colorado, that stunned the country. Although neither the first nor the worst school shooting in the United States, Columbine galvanized national attention around the issue of school violence in a way other incidents had not. Tragically, Columbine is often the first incident mentioned in a decades-long litany that includes catastrophic violence at schools including Virginia Tech, Sandy Hook Elementary, Marjory Stoneman Douglas High, and Robb Elementary.

The shooting

The shooting was carried out by Eric Harris, 18, and Dylan Klebold, 17. On April 20, 1999, they entered Columbine High School in Jefferson county, Colorado, with semiautomatic rifles, pistols, and explosives. In less than 20 minutes they killed 12 fellow students and a teacher and wounded 21 others. The violence came to an end when Harris and Klebold died by suicide. One of the students who was shot in the attack died in 2025 from complications related to her injuries. Her death was ruled a homicide, raising the official count of the victims killed in the shooting to 14.

A specific motive, beyond extreme hatred, was never identified, but evidence found after the shooting made clear that the pair had been planning a deadly assault for at least a year. In Harris’s yearbook from the previous school year, Klebold wrote “the holy April morning” and “killing enemies, blowing up stuff.” In fact, it appeared that the pair intended to blow up the school cafeteria, with shooting being a secondary method of murder. Officials found two propane tank bombs in the cafeteria; had they detonated the death toll would have been much worse.

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Response

The Columbine tragedy dominated headlines nationally and internationally. There was strong criticism of the slow police response. Despite the fact that the shooting ended by noon, police and sheriff’s deputies, believing there was continuing danger, did not enter the school for several hours, during which time some victims bled to death.

Columbine became a focal point in ongoing national debates over gun regulation, school safety, and the influence of media and technology on youth behavior. The shooting prompted many school districts to adopt heightened security measures, including surveillance systems, controlled access points, and the presence of school resource officers. Law enforcement agencies also revised their response strategies, increasingly emphasizing rapid intervention in active shooter situations. However, problems with police responses continued, particularly in the shootings at Marjory Stoneman Douglas High in Florida in 2018 and Robb Elementary School in Texas in 2022.

The Department of Education and the Secret Service embarked on research to identify what provokes school shooters, finding that many feel persecuted and are looking for attention, often telling others about their plans. Pres. Bill Clinton proposed what he called “common sense gun control” that would have required background checks, gun locks, and a ban on importing large magazine clips. It failed to win congressional approval. Similar calls for legislation would follow other school shootings, including the Sandy Hook shooting in which 20 first-graders were slain in Connecticut in 2012. It was not until 2022, in the wake of the Uvalde, Texas, school shooting, as well as other mass shooting events, that meaningful gun safety legislation at the federal level passed Congress.

In its report on the Columbine shooting, the Jefferson County Sheriff’s Office ended with a moving plea, one that would be eerily echoed in the decades to come.

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While this report establishes a record of the events of April 20, it cannot answer the most fundamental question—WHY? That is, why would two young men, in the spring of their lives, choose to murder faculty members and classmates? The evidence provides no definitive explanation, and the question continues to haunt us all.

While our community struggles with that question and grieves those who were lost, we remain united in one hope—that our nation shall never see anything resembling the tragedy at Columbine High School again.

The victims

Klebold and Harris killed 14 people, 13 students and one teacher. They were:

• Cassie René Bernall, 17
• Steven Curnow, 14
• Corey DePooter, 17
• Kelly Ann Fleming, 16
• Anne Marie Hochhalter, 17 when she was shot; she died at age 43 in 2025.
• Matthew Kechter, 16
• Daniel Mauser, 15
• Daniel Lee Rohrbough, 15
• William (“Dave”) Sanders, 47
• Rachel Joy Scott, 17
• Isaiah Emon Shoels, 18
• John Tomlin, 16
• Lauren Townsend, 18
• Kyle Albert Velasquez, 16