James Alan Fox is a criminology professor at Northeastern, so we assume he has data to back up the statements in his brief article, "Top Ten Myths About mass Shootings," posted at the Chronicle of Higher Education. It's well worth reading, and depressing as hell.
We've been hearing, post-Sandy Hook, a fair amount of panicky talk about how to keep things like this from happening. At its worst,* this boils down to partisan boilerplate, in which one side blames guns and the other blames crazy people. (Ironically, the side that blames crazy people has also been deeply engaged in slashing government mental-health expenditures, but that's another story).
Fox points out that a lot of what we've been hearing is nonsense. Mass shooters are typically turned so completely inward on themselves that they would never seek psychiatric care, for example; they are so mentally prepared and emotionally committed to their mission that panicky and underprepared armed guards are likely to harm innocents without stopping the guilty; a new assault weapons ban is unlikely to affect automatic pistols, which are the preferred weapon used in these killings.
And on and on, because he packs a lot of bad news into a few paragraphs.
The most depressing thing is that Fox offers no prescription. He does not seem to think that there is much we can do, really -- at best, we might shave a few degrees of lethality off the top. Stronger gun laws and better mental-health services may save a few lives, but ... don't get your hopes up.
*Actually, partisan bickering is not the very worst level of public debate. The very worst is the despicable "Sandy Hook Truther" movement, which claims the shootings are a hoax. We expect these people are also Holocaust deniers and child molesters.