The beginning of the week featured another horrible mass shooting in America. This time at a bank in Louisville, Kentucky.

That's why I wanted to bring on one of the leading experts currently studying mass shootings. Metro State University Professor James Densley is one of the co-founders of The Violence Project, which has the most detailed and comprehensive database of mass shootings dating back to 1966. He is also the co-author of the book by the same name that outlines potential real-world solutions to the phenomenon.

Professor Densley explained why he believes the count they use, which only includes public attacks where four or more people are killed for reasons unrelated to other criminal conduct, gives the most accurate understanding of mass shootings. He said it's important to properly define terms when you're attempting to seriously study a problem and identify trends so you can craft solutions.

He laid out some of the common patterns seen in the lives of mass shooters before they carry out their attacks. For instance, he said most shooters have a long history of abuse and trauma before they decide to do the unthinkable. And the shootings almost always follow an inciting incident that sends the shooter into a crisis state.

Densley argued that a potential attacker could be "off-ramped" at any point along that path, whether it's after they first experience abuse or after they begin experiencing an inciting crisis. What's necessary is for those who recognize the warning signs to step in and do something to help. And that resources to help are made available and known to those looking to carry out that kind of intervention.

But those aren't the only interventions Densley believes are necessary. He said firearms restrictions of some kind should be part of the equation as well, especially for those showing warning signs they may be a threat to themselves or others. We go back and forth on why gun-rights advocates and gun owners are not as open to those ideas as Densley would like them to be.

Ultimately, Densley said he believes mass shootings are not an inevitability and can be prevented through action on the individual and societal level--even if not everyone agrees on every aspect of the solutions he proposes.

Plus, Contributing Writer Jake Fogleman and I discuss a new win in court for marijuana users who want to own guns.

Special Guest: James Densley.