Gun extremists like to portray the perpetrators of mass shooters as known criminals that should have been identified and stopped. That is a damn lie. Like millions of people in the United States, mass shooters often have anti-social behavior and/or involve themselves in hate-filled social media posts. Almost all of those people will not become a mass murderer. None of the mass shooters are identified as criminals until after they have picked up a gun and killed people.

Here is a list of the 20 worst mass shootings and indicators of instability prior to their crime:

Millions of People Are Mentally Ill, Only a Few Kill

In some of the instances listed above the mental illness was known but was not an accurate predictor of the actions taken by the perpetrator. Almost all of the perpetrators were U.S. citizens, male, had easy access to guns, and/or was obsessed with gun ownership.

The five worst events have occurred after the ban on assault rifles was allowed to expire in 2004. Half of the top 22 mass shootings have happened in the last 18 years and the other half occurred in the 50 years prior.

More Guns, More Deaths

The simple fact is the explosion of gun ownership in the past three decades has resulted in an explosion of gun deaths. We are not safer now than we were 50 years ago, and while the funding for mental illness treatment is a factor, if guns weren’t easily accessible, the mentally ill would not have the opportunity to use them.

There are only three mass shooting events among the top 22 where the guns were not legally obtained. In two cases the guns were obtained because the criminal records of the perpetrator were not on record as they should have been. In the Columbine High School shooting, the two teenagers used friends to buy them guns. The other 19 events were people who had easy, legal access to the guns and if they hadn’t had that access, I wouldn’t need to write this article.