The Columbine Effect Chart & The Columbine Script List (1999 - 2026)
The "Columbine Effect Chart" was created by clinical psychologist Peter Langman and it has not been updated after 2019 bc he thought new perpetrators could seek being included in his chart because it's used by FBI. Langman's perpetrators database is also considered as primary source by FBI. Langman criteria is strict: he only includes a perpetrator in his chart if there is an explicit written or oral mention of Eric Harris or Dylan Klebold so when perpetrators don't mention them explicitly, Langman excludes them.
USA
The "Columbine Script" refers to a social and cultural blueprint for mass/school shootings established by Eric Harris & Dylan Klebold. This term and its list were created by forensic psychologists, criminologists & sociologists of "The Violence Project", a US federal funded reserch center & FBI use their database as primary source too. The Columbine Script List include all perpetrators around the world that replicate Harris & Klebold's tactics, personal narratives, patterns, symbology, physical gestures, weaponry, explosives, literature, quotes, music, psychosocial profile, schedules, aesthetics, rituals, clothing, methodology, fame seeking, record breakings, content comsumption or internet searches related to Harris and Klebold.
It follows the real time order by year: from the earliest event (by perpetrator's name) to the latest within each year.
1999 : Todd Smith, T.J. Solomon, Martin Peyerl and Seth Trickey.
2001 : Andy Williams and Jason Hoffman.
2002 : Robert Steinhäuser.
2004: Rafael Solich.
2005: Robert C. Bonelli, Jeffrey Weise and Patrick Amstrong.
2006: James Newman, Alvaro Castillo, Kimveer Gill, Bryan Draper & Torey Adamcik, Eric Hainstock and Bastian Bosse.
2007: Chad Escobedo, Seung Hui Cho, Pekka-Eric Auvinen, Kenton Astin and Matthew Murray.
2008: Steven Kazmierczak, Morné Hamse and Matti Saari.
2009: Tim Kretschmer and Justin Dorset.
2010: Bruco Eastwood.
2011: Tristan van der Vlis.
2012: Trey Sesler, James Holmes, Robert Gladden Jr. and Adam Lanza.
2013: Gonçalo A., Jose Reyes and Karl Pierson.
2014: Darion Aguilar, Alex Hribal, Geddy Kramer, Aaron Ybarra and Jered &Amanda Miller.
2015: Robert & Michael Bever, Vester Flanagan, Chris Harper-Mercer and Anton Pettersson
2016: Jesse Osborne.
2017: Killian Barbey, Randy Stair/Andrew Blaze, Mikhail Pivnev, Caleb Sharpe and William Atchison.
2018: Lev Bijakov & Alexander Buslidze, Nikolas Cruz, Artyom Tagirov, Sky Bouche, Dimitrios Pagourtzis , David Moore, Faisal Hussain and Vladislav Roslyakov.
2019: Guilherme Monteiro & Henrique de Castro, Devon Erickson & "Alec" McKinney, Marec Nowak, M.A.C. and Daniil Pulkin.
2020: José Angel Ramos Betts, Łukasz Wach and Daniil Monakov.
2021: IInaz Galyaviev and Aidan Ingalls.
2022: Ethan Blair Miller, Artyom Kazantsev and Gabriel Rodriguez Castiglione.
2023: Aiden Hale and Phasid Trutassanawin.
2024: Dylan Butler, Damian Haglund, Arda Küçükyetim, Nicholas Prosper, Roman G. and Natalie/Samantha Rupnow.
2025: Owen Lawrence, Arthur A., Desmond Holly, Muhammed Nazriel Hidayat and Timofey Kulyamov.













