Editing Columbine High School massacre (section)

==== The FBI's theory ====
The FBI concluded that the killers had [[Mental disorder|mental illnesses]], that Harris was a [[Clinical diagnosis|clinical]] [[Psychopathy|psychopath]], and Klebold had [[Major depressive disorder|depression]].<ref name="slatecol" /> Dwayne Fuselier, the supervisor in charge of the Columbine investigation, would later remark: "I believe Eric went to the school to kill and didn't care if he died, while Dylan wanted to die and didn't care if others died as well."<ref>{{Harvnb|Klebold|2016|p=172}}</ref>

In April 1998, a year prior to the shooting, as part of his diversion program, Harris wrote a letter of apology to the owner of the van he and Klebold broke into earlier that year.<ref name="dive" /> Around the same time, he derided the owner of the van in his journal, stating that he believed he had the right to steal something if he wanted to.<ref name="HJ41298">{{Harvnb|Cullen|2009|p=260}}</ref><ref>{{cite web |url=http://www.columbine-online.com/journals/columbine-eric-harris-big-lie.htm |title=Eric's big lie |last=Cullen |first=Dave |publisher=Columbine Online |access-date=October 15, 2014 |archive-url=https://web.archive.org/web/20110119045203/http://www.columbine-online.com/journals/columbine-eric-harris-big-lie.htm |archive-date=January 19, 2011}}</ref> By far the most prevalent theme in Klebold's journals is his wish for suicide and private despair at his lack of success with women, which he refers to as an "infinite sadness".<ref>{{Harvnb|Klebold|2016|p=159}}</ref> Klebold had repeatedly documented his desires to kill himself, and his final remark in the Basement Tapes, shortly before the attack, is a resigned statement made as he glances away from the camera: "Just know I'm going to a better place. I didn't like life too much."<ref name="tape333">{{Harvnb|Cullen|2009|p=349}}</ref><ref>{{Harvnb|Klebold|2016|p=137}}</ref>

The FBI's theory was used by [[Dave Cullen]] for his 2009 book ''[[Columbine (book)|Columbine]]''. Harris was depicted as the mastermind, having a [[Messiah complex|messianic-level]] [[superiority complex]] and hoping to demonstrate his superiority to the world. Klebold was a follower who primarily participated in the massacre as a means to simply end his life.<ref name="slatecol" /><ref>{{Harvnb|Klebold|2016|pp=159–160}}</ref>

This theory has been met with criticism.<ref name="Salon" /> Critics cite the fact that Klebold, not Harris, was the first to mention a killing spree in his journal.<ref name="Block" /><ref>{{cite web |last=Roberts |first=Michael |date=May 7, 2009 |title=Author Jeff Kass on how his Columbine theories differ from Dave Cullen's |url=https://www.westword.com/news/author-jeff-kass-on-how-his-columbine-theories-differ-from-dave-cullens-5884190}}</ref> They also cite evidence that Harris was depressed as well, such as his prescription for [[antidepressants]] mentioned below.<ref>{{cite book |last1=Sheffield |first1=Anne |title=Sorrow's Web: Overcoming the Legacy of maternal Depression |date=2001 |publisher=Simon and Schuster |location=Manhattan, NY, USA |isbn=978-0-7432-1318-9 |page=247}}</ref>