Is Mass Murder on the Rise?

"Yes," says Todd McGhee, who pioneered new security measures at Logan Airport, post 9/11 and later co-founded Massachusetts-based Protecting the Homeland Innovations LLC.

"No," says Jack Levin, author of "Extreme Killing: Understanding Serial and Mass Murder."

Each can defend his answer.

McGhee has studied the phenomenon since 2009 and says his research shows an increase in firearms and IED deployment in mass murders. "I think with the different things going on in our political landscape and in our economy, people are taking it upon themselves to justify their reactions and strike out against the mainstream political landscape," he says. "People are choosing a very violent way to express their views. We are seeing access to weapons made easier because of the Internet. The Anarchist Cookbook can be purchased online and used to make IEDs in the privacy of our own homes. The flow of information is changing our social and political landscape. If people are passionate about their views, they can quickly arm themselves and do something about it."

Levin disagrees. "It's not happening more often. There are about 200 victims of mass killings in this country every year and that has been the case since the early 1970s. It varies a little from year to year if there is an event with a particularly large body count. But overall as a general trend mass murders are about the same in number every year."

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