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Danny Cevallos: Research confirms what we've long known: Juveniles are immature

Danny Cevallos is a CNN legal analyst and a criminal defense attorney practicing in Pennsylvania and the U.S. Virgin Islands. Follow him on Twitter: @CevallosLaw. The opinions expressed in this commentary are solely those of the author.

(CNN) In the wake of the latest tragic shooting, in a Louisiana theater by a nearly 60-year-old killer, we now may be in an era of lone gunmen and mass killings. Massacres like these are so unpredictable it's impossible for us to know how to avoid them. Should we steer clear of theaters? Churches? Military bases? Our primal fears may keep us from these places, even though our rational brains should know better: Millions of people frequent these establishments each day and face no threat.

And then there's the issue of WHO we should be avoiding. How do we know who fits the profile of a shooter? Is a 59-year-old male a typical mass killer? As a group, who is more dangerous? Younger people or older people?

Actually, the question should really be: Are younger or older males more of a threat? Because if we're looking to have a frank discussion instead of trying to tiptoe through a politically correct minefield, then let's not waste time talking about women of any age as a significant homicidal threat. You don't need a commissioned, funded study to simply count and compare the numbers of male criminals, inmates and prisons compared to their female counterparts. It's not even close: Men are more dangerous than women

Danny Cevallos

But what about age? In the last few years, we've had a number of high-profile, completely senseless mass shooters: