Mass shootings are rising. They're committed by lunatics who suddenly snap and start shooting at random. If only we had better gun laws or mental health screenings, we wouldn't have so many tragedies.

Stop. Almost everything you think you know about mass shootings is wrong. This morning, I sat down for an IM interview with Northeastern University Criminologist James Alan Fox, who has been studying mass murder for years, and has authored two books on the subject: Extreme Killing, and Violence and Security on Campus.

Megan: First of all, thanks for doing this. Second of all, can you start off by talking a bit about yourself? How did you start studying mass shootings?

James Alan Fox: I started studying mass murder in the early 1980s (along with Northeastern University colleague Jack Levin) to see if there were any common traits and characteristics to the crimes or the perpetrators. There had been a pervasive sense back then that mass murderers were crazed lunatics who suddenly snapped, went berserk, and killed indiscriminately. By studying 42 cases that had occurred in recent years (recent back then, anyway), we found that many common assumption were quite off the mark

Megan: How so?

James Alan Fox: Mass murderers are extraordinarily ordinary.

Most mass killers kill people they know, with a clear-cut motive. They typically plan their crimes in advance, often weeks or months in advance. They are calm, deliberate and determined to get justice for what they perceive to be unfair treatment.

The idea that they suddenly snap actually makes little sense. They snap and just so happen to have 2 AK-47's and 2000 rounds of ammunition around for just such an occasion? Hardly.

Megan: We can see the evidence of planning, but how do we know their motive? Do they typically leave behind an explanation?

James Alan Fox: Yes, they often do leave behind an explanation, or articulate it if they survive. Or they make it clear while they are doing their shooting.

And, by the way, they can be very selective, e.g., Joseph Wesbecker passed by some people in his way (saying, "not you, Joe") while killing 8 and wounding 12. He had a sense of the good guys versus the enemy.

Another example is a gunman in Wakefield, MA (Michael McDermott), who went to his workplace during Christmas to bring his weapon there while no one was around. The next day, he went to work and started shooting--but only those in HR and accounting whom he blamed for teaming up with the IRS to garnish his wages for unpaid taxes.

Most of the time, the motive is to get even with those they hold responsible for their misfortunes. Usually people at work or at home, or sometimes a class of people (women, Jews, immigrants, whites, blacks, etc) . . . so the victims are chosen randomly, but not the type of victim, or the place to find them.

The rarest form is the completely random attack committed by someone who in their paranoid thinking suspects that the whole world s corrupt and unfair.

Megan: So they plan for a long time and they typically see themselves as victims of some sort of terrible injustice. Is that why so many of these shootings happen at school or work? I remember high school as a place of great injustice . . .

James Alan Fox: Yes, schools, workplaces, and residences. And do you ever notice how often witnesses say "he was smiling; and looked so calm" That's because they had been through this in their mind for so long that they’re extremely comfortable with the plan.

Actually there have been adults who return to their old school where things hadn't gone so well for them. Of course, we think of Adam Lanza. But a very similar case occurred back in 1989. Patrick Purdy killed 5 and wounded 29 at an elementary school in Stockton CA. That case didn't quite have the same impact for several reasons. One, of course, is that the victims were poor Southeast Asians, not upper middle class white folks from a nice community in CT.

And, back then, mass shootings weren't covered live as they unfolded. The technology didn’t exist back then nor did the 24 hour cable channels who could devote all their attention to it.

Megan: That brings up a question that some people have been asking about media coverage.

Obviously, it makes the tragedies more immediate. But does it also encourage copycatting? Does the 24-hour news cycle make it more likely that we'll have follow-on events?

James Alan Fox: To some small degree. Copycatting does exist, of course. And the nature of the coverage matters. There is a big and important distinction between shedding light on a crime and a spotlight on the criminal.

For example, the attention given to Sueng Hui Cho (VA Tech) with his fearsome pose. Not just in the tabloids, but above the fold in that NY paper whose motto is "all the news that's fit to print". It does turn monsters into celebrities.

Take the coverage of Columbine: cover of Time with the pictures and headline "Monsters next door." Sure, as adults we saw Klebold and Harris as monsters, but there would have been a few alienated adolescents who saw them as heroes . . . not only did they get even with the jocks, and the nasty teachers, but they're famous for it.

Megan: What evidence do we have about copycatting? Are there cases where we can document the killers being inspired by other famous shooters?

James Alan Fox: Yes . . . For example, back in the 1980s when we had the string of postal shootings, there were a couple who spoke or wrote about other postal rampages that had preceded their own. Also, take the case of Jamie Wilson of South Carolina. He was a big fan of Laurie Dann (a school shooter in Winetka, Illinois). He talked about her all the time, had clippings about her case.

After he went on a shooting spree similar to hers, the police went to his apartment and found photos of Dann (on the cover of People) around his apartment. Joseph Wesbecker left open on this coffee table a magazine story (I think it was Newsweek but it may have been Time) about a mass shooting at the McDonald's in San Ysidro, CA. He then went to commit his own rampage...

And speaking of People Magazine; Levin and I did a study a few years ago content analyzing the covers of People from its inception. It started out featuring people who did good things and deserved attention, but soon trended toward murderers and rapists. Jeffrey Dahmer was on the cover several times....even made the list of 100 moist intriguing people of century

Megan: I had not idea. That's pretty disturbing

James Alan Fox: They have improved in the past few years.

Megan: I’d like to talk about how we count mass shooters, which has been a bit of an issue over the last week or so. Mother Jones had a widely cited analysis showing that mass shootings are on the rise. But you've disputed that, saying that their count is unreasonably restrictive.

James Alan Fox: Yes, that's right. If one examines the full range of cases--all shootings with at least four victims killed, the numbers have been trendless. Over the past 35 years, there has been an average of jut under 20 incidents per year. Of course, most were not as well-publicized, or as large-scale, as Sandy Hook.

I understand that Mother Jones was trying to isolate "random" massacres, but their criteria were sometimes arbitrary and not even applied consistently. For example, they wanted to limit their pool to cases involving a lone gunman, but made exceptions for two well-known school shootings (each committed by a pair of students) that they wanted to include.

Given how difficult it to accomplish the task of defining "random", I would opt for including all mass shootings. Besides, if 7 or 10 or 14 are killed in a not-so-random shooting spree, is this any less important or devastating?

I do applaud their effort to build a database that includes details on each case, but they would have been better off not limiting he pool based on questionable criteria

Megan: It seems that they were trying to control for the shootings by young men in gangs. But one question is whether they're really that different: are gang shootings purely economic? Or are they, too, often about injustice and disrespect?James Alan Fox: Great question (and observation). Gang shootings are often about revenge, not at all distinct from someone who avenges a termination or missed promotion by shooting up his worksite

Megan: In general, I was taught that either you say "we're including anything that meets a certain number of these criteria" or "we're excluding anything that doesn't meet all these criteria". Mother Jones is mostly using criteria of exclusion, except when it seems to produce some sort of absurd result (like excluding Columbine), at which point they shift to criteria of inclusion. I've always been taught that this is a big no-no in analysisJames Alan Fox: I would agree that this is improper.

I'm not making a distinction between inclusion criteria v exclusion criteria. My concern is that whatever decision rules are to be employed need 1) to be clear-cut and unambiguous, and 2) followed as closely as possible.

If you wanted to create a database and analysis of family massacres, you'd be on solid footing. Decide on a definition of massacre (by victim count) and decide whether family includes extended kin or not.

If you wanted to write a book about workplace massacres, you would need only to decide whether to include shootings by clients/customers and other intruders, in addition to those by current or former employees.

Megan: So you have been saying that many of the most popular remedies for mass shootings won't work. They aren't all identifiably crazy before the shooting, so mental health screenings for gun buyers won't stop them. Neither will waiting periods, because they're long-term planners. And restricting certain scary guns (an "assault weapons ban") won't have much effect, because they'll just pick another gun.

Which leaves the question: is there anything that would work?

James Alan Fox: Let me say, first, that expanding mental health services would be a good thing, even though it would have little effect on mass murder, because these guys typically see the problem in someone else, certainly not themselves.Also, certain sensible gun policy changes would take a bit out of ordinary crime, but at most a nibble out of mass murder.

These are very determined and deliberate people who will almost always persevere no matter what impediments we place in their way.That doesn't mean we shouldn't try. We will probably enhance the well-being of countless Americans in the process. So mass shootings may motivate us to take important steps: they are the right things to do, but we’re not so much doing them for the right reason.

We have seen a tremendous eclipse of community. People no longer know their neighbors, much less are aware of when they may lose their job or are kicked out of school. The best thing we can do is be proactive in intervening in the lives of those around us who are in need of support. We need to assist people who are troubled before they make trouble

As an aside... It concerns me at some level that we know are eager to help those with psychological problems when we see what happened in Sandy Hook and Aurora. We should want o help those who suffer because we are concerned about THEM, not just because we are concerned about those they might kill

Megan: Last question: is there any question I should have asked you, but didn't?(It's okay to say no!)

James Alan Fox: Yes, there is one more thing

I'm often asked if there is a profile of the mass murderer. Well, there is. Typically a white male who has a history of frustration and failure, who is socially isolated and lacking support systems, who externalizes blame onto others, who suffers some loss or disappointment perceived to be catastrophic, and has access to a powerful enough weapon (usually, but not necessarily a gun).

The follow-up question I usually get is whether we can therefore identify mass murderers in advance, and the answer is a resounding "no."

Although there is a profile, thousands of citizens fit the profile yet will never hurt anyone, much less kill a crowd of people.

"And what about the warning signs?" people ask. Well there are warning signs, but they don't come into focus until after the fact when hindsight is 20/20. There are "yellow flags" that only turn into red ones once the blood has spilled.

Part of the reason for lack of predictability is the rarity of mass murder. Rare events simple cannot be predicted in a reliable fashion. For example, plane crashes typically happen in bad weather, but bad weather is not a reliable predictor of a plane crash.

The danger in trying to round up all those who might have the potential for mass murder is that it could even intensify their sense of persecution and precipitate the very act we are trying to prevent. We should intervene when needed, but not in a way seen as punitive.

So there are things we should do: sensible gun policies, expanded mental health services, proactively reaching out to those who need our support, changing the tone of media coverage to avoid playing up the perpetrator as someone worthy of attention. However, when people say we need to do X, Y, or Z to ensure that something like Sandy Hook will never happen again, well, they should prepare to be bitterly disappointed.

Unfortunately, mass shootings will occur even if we take these steps. We cannot eliminate the risk; the best we can do is reduce it a bit.

And if that happens (reduce the risk a bit), how will we know that we did? If mass shootings drop in 2013 (which they will likely do), does that mean we made a difference? Or just that a spike was followed by a more moderate level of occurrence? If the number of mass murders drops from 20 per year to about 16 per year for a few years in a row, does that mean that the trends is downward? Or that it is a random fluctuation from the average?

We may never know if our preventive efforts make a difference, but that shouldn't stop us from trying. My only fear is that the momentum following Sandy Hook will dissipate and disappoint those of use who are hoping for change in practice or policy

Want to learn more? You can find James Alan Fox on his blog, Crime and Punishment.