Mass Shooters who were not diagnosed with any disorder or mental illness

Charles Andrew Williams: Survived the shooting and was not diagnosed with anything during the trial, at least to my knowledge.

Mitchell Johnson & Andrew Golden: Survived their shooting. Because of their age, their psychiatric examination was not made public. According to the book "Rampage. The social roots of school shootings", there were people who had access to this reports and commented, that there was no major disorder or illness noted in the examination.

T.J. Lane: Survived his shooting. He was not diagnosed with anything during the trial, at least to my knowledge.


To be honest, that are all cases, in which a shooter did not seem to suffer from a personality disorder or a mental illness, that I know of.
Hence, it is hard for me to believe, that mental illnesses among mass shooters are "rarely" the case.

Robert Bales - US Army Staff Sargent who shot and killed 16 and injured 6 (I believe it was later changed to 15 - 7 after one victim had been double counted)- Known as The Kandahar massacre.
Bales was sentenced to life in prison without parole. In 2010 he was treated for a traumatic brain injury but was deemed healthy. He had a history of "incidents" involving violence and had attended an anger management class. Apparently he had been drinking the day of the massacre and there are reports of him abusing steroids.
At trial it was reported Bale had no history of mental disorder and had undergone extensive mental health screening in 2008 in order to become a sniper. I could not find any mention that he has since been diagnosed with anything. It was widely reported that he just "snapped."

Brothers Antonio and Emilio Izquierdo shot and killed 9 people in Spain after opening fire in the street. The event was known as Puerto Hurraco massacre. Both were sentenced to 684 years in prison.  An insanity plea was ruled out by the judge. After serving 20 years Antonio hanged himself in prison, Emilio died of a heart attack in 2006. Interestingly their sisters were in a psychiatric hospital for 15 years after been diagnosed with paranoid delusions. They also had another brother who beat someone to death and was sent to a psychiatric hospital where he died. Seems like they had a family history of mental illness but i don't see anything that indicates they were ever diagnosed with anything. The reason for the shooting was considered to be revenge for an old dispute involving land.

This is an interesting article and relevant to this topic: [You must be registered and logged in to see this link.]

Eric Harris and Dylan Klebold we’re not diagnosed with any disorders or illnesses during there life though they were analyzed and posthumously diagnosed by the FBI following Columbine but the FBI’S analysis and conclusion has attracted considerable criticism and skepticism so I wouldn’t say it’s definitive.

Guilherme Taucci and Luiz henrique were not diagnosed with any disorders. But clear signs that they could suffer depression/another tipe of disorder