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Columbine High School Shootings Investigation Records, April 20, 1999

Identifier: Series-121

Scope and Contents

Collection contains a set of 23 CD and DVDs containing digitized copies of all investigative files, documents, reports, audio and video recordings, images, and drawings released to the public in connection with the investigation of the shootings at Columbine High School on April 20, 1999. Listed next to the title of each CD or DVD is the date those particular records were released to the public.

Paper copies of the Investigative Files found on CD #9 contain reports, interviews, and witness statements with victims, students, teachers, and others. They are organized in groups by physical location at the time of the shootings then alphabetically by name.

According to the Jefferson County Sheriff’s Department’s website accessed in 2016, all remaining Columbine evidence, including the “Basement Tapes” were destroyed in early 2011.


  • Event: April 20, 1999


Conditions Governing Access

Archives collection material is non-circulating, requires staff retrieval and is available for use by appointment in the reading room.

Conditions Governing Use

Laptop needed to view CDs and DVDs.

Biographical / Historical

On a sunny spring day in April 1999, a suburban high school in Jefferson County, Colorado, found itself under attack by two of its own. In less than 15 minutes of the first lunch period on that Tuesday, two student gunmen killed 13 and wounded 21 before they turned the guns on themselves.

Columbine High School is one of three in the unincorporated southeast portion of Jefferson County. The county itself lies on the west side of the Denver metropolitan area and is the most populated county in the state. The large unincorporated region along the county’s southern plains and foothills had a population of nearly 100,000 residents in 1999 - 1,945 of who attended Columbine High School.

The two student gunmen were Eric Harris and Dylan Klebold. Their plans for attacking the school, recovered by investigators after the tragedy had taken place, evolved over one year’s time. In those plans, Klebold and Harris outlined a mission to kill as many students and faculty as possible. They would set off destructive bombs inside the school and then shoot any survivors trying to run out. Bombs inside their cars would explode later, killing law enforcement, fire or medical personnel responding to the scene.

When many of the Columbine students heard what sounded like pop guns coming from outside the cafeteria during the first lunch period, they thought that senior prank day had come. School-wide pranks initiated by graduating seniors were a tradition throughout the United States, and up to that point Columbine’s seniors, ready to graduate in just four weeks, had not participated in any such activity. It seemed right to students who heard the first few shots that, as it was toward the end of the school year, prank day was finally upon them.

But it wasn’t a prank. Not when two hate-filled students, heavily armed with firearms and bombs, chose April 20, 1999, as the day to attack and kill students and faculty at their school.

(History note taken from the Foreword to the Sheriff’s Office Final Report.)


5.00 Cubic Feet (12 Boxes (10 DOC, 2 SLD, 23 CD/DVDs)) : Legal size boxes

Language of Materials



Police reports, interviews and witness statements of victims, students, teachers and others, and set of 23 CD/DVDs containing digitized copies of all investigative files, documents, recordings, images and drawings released to the public in connection with the investigation of the shootings at Columbine High School in Littleton, Colorado, on April 20, 1999.


Arranged numerically. Disks numbered by Jefferson County Sheriff's Office.

Immediate Source of Acquisition

The Jefferson County Sheriff’s Office provided a copy of its Final Report on CD to the Archives when it was released in 2000, and a set of the JCSO 911 and Dispatch Audio CDs was given in 2004. Paper documents were converted to CD by the Sheriff’s Office Records Unit to provide a user-friendly format. A complete set of all CDs and DVDs was provided to the Archives in July 2011. Binders containing paper copies of the Investigative Files found on CD #9 were transferred to the Archives in February 2016 by the Jefferson County Public Information Office.

Existence and Location of Originals

All original material is held by the Jefferson County Sheriff's Office. Copies of Columbine records released by the Jefferson County Coroner’s Office, El Paso County Sheriff’s Office and Jefferson County District Attorney’s Office may be obtained directly from those agencies.

Related Materials

Series 131: Ephemera Recovery Photographs; Media Articles

Processing Information

Processed by Ronda Frazier in 2013. Reprocessed in 2016.

Language of description
Script of description

Repository Details

Part of the Jefferson County Archives Repository

3500 Illinois Street
Suite 2350
Golden CO 80401 United States