Free Minds & Free Markets

Choose Your Own Mass Shooting Statistics

From Mother Jones to the Mass Shooting Tracker: where activists and reporters get their stats

If you want size without context, the Mass Shooting Tracker is perfect for you.The Washington PostIf you follow the news right after a crime like yesterday's mass murder in California, you've probably encountered the Mass Shooting Tracker. A crowdsourced project with roots in a Reddit subgroup, the tracker is the source for such headlines as "The San Bernardino shooting is America's 1,044th mass shooting in 1,066 days" (at Vox) and "The San Bernardino shooting is the second mass shooting today and the 355th this year" (at Wonkblog, the original Vox). Its numbers turn up in news outlets across the country, and those numbers always sound enormous.

This marks a sharp change from the way the issue was discussed a few years ago. In the wake of the Sandy Hook massacre, the go-to source for places like Wonkblog was Mother Jones' "Guide to Mass Shootings in America," which first appeared in 2012 and has been periodically updated since then. It currently lists 72 incidents since 1982, a rather smaller figure than the tracker provides. That's because Mother Jones uses a much narrower definition of "mass shooting," trying to focus on crimes like Columbine without roping in any robber who fires a gun at several people. But Mother Jones also lists more incidents in recent years than earlier. If the Mass Shooting Tracker alarms people by showing them a big number, the Mother Jones list alarms people by suggesting such shootings are happening more frequently.

When skeptics started challenging Mother Jones' list, they usually pointed instead to yet another source: the FBI, which has more or less defined a mass shooting as a gun crime where four or more people are murdered. (*) The FBI stats showed many more mass-shooting incidents and casualties than Mother Jones did, but they also undermined the idea that the numbers were shooting upward; these figures zig-zagged erratically for decades, sometimes rising and sometimes falling, without any discernible trend. Mother Jones argued that its approach was better because it didn't mix "mass shootings in public places with a far more numerous set of mass murders that are contextually distinct—a majority of which stem from domestic violence and occur in private homes."

The Mass Shooting Tracker, by contrast, uses an even more expansive definition than the FBI's: not incidents that leave at least four people killed but incidents in which at least four people are hit.

Obviously, this gives you a bigger total than any of the other measurements. But while the feds' stats go back years, the Shooting Tracker begins in 2013—and because its data come from press accounts rather than police records, it's a somewhat shaky source for year-to-year comparisons anyway. (This is also a problem with the Mother Jones list, which tends to undercount shootings that did not happen relatively recently. The amount of press coverage that different sorts of crime attract inevitably varies over time.) So basically, the Mass Shooting Tracker offers the biggest available estimate of recent shootings with no way to see if the crimes that fit its definition are becoming more or less common.

If you want to get a sense of both the size of the problem and the trend over time, your best bet is a Congressional Research Service study released this past summer. It looks both at mass shootings as broadly defined via the FBI and at Sandy Hook-style public shootings; for the latter category, it relies not on the Mother Jones count but on a more comprehensive dataset assembled by the criminologist Grant Duwe. (Rather than starting with a search of news accounts, Duwe begins with the FBI's homicide data to find out when and where mass killings happened, then uses the available media reports to fill in the details.) I described that paper's conclusions in detail here, but these are the highlights:

  • Mass shootings were slightly more common, and killed a larger number of people, in 2009-2013 than in the previous two five-year periods. The congressional study attributes both increases largely to one outlier year, noting that 2012 was unusually bad.
  • Few mass shootings are mass public shootings.
  • More people die in mass public shootings now than in previous decades, but if you adjust for population growth that increase basically disappears.

There will always be many ways to slice the data, and it's not a bad thing that there are multiple measurements out there, as long as readers understand what precisely each one describes. But the most important figures of all are the ones you get if you cast a really wide net—wider even than the Reddit group's—and look at the rates for gun violence of all kinds. In that case, the numbers are clear: Both fatal and nonfatal firearm crimes have dropped dramatically over the last two decades.

(* Strictly speaking, this is how the FBI has defined mass murder, with the added requirement that the killings be committed with a firearm. There is no official FBI definition of "mass shooting.")

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  • Fist of Etiquette||

    If you count whitetail deer, as I do, then Monday was the worst mass shooting day of the year in Pennsylvania.

  • Sudden||

    But the animists have animus towards any metric that doesn't count any miss as a mass shooting

  • Haven Monahan||

    Why are "mass shootings" any more important than homicide totals?

    If you've just been murdered, does it really matter whether it was a bullet that killed you or whether other people were killed in the same incident?

  • tarran||

    The proggies pushing it are afraid of mass shootings because they don't believe themselves to be in danger of any other kind.

    They have no guns. They live in neighborhoods were the crime rate is low. They truly believe that if they call 911, Andy Griffith and Lt Kate Becket will ride to their rescue.

    So they don't worry about someone breaking into their house at night to rape their daughter, or to get at their bank cards or to kidnap them for ransom.

    Many of them haven't developed the maturity to cope with risk; they want all risks to be eliminated so that any mistakes they make or misfortunes they suffer are comparatively little ones.

    And this sort of lurid thing strikes fear into their hearts.

  • LynchPin1477||

    Many of them haven't developed the maturity to cope with risk; they want all risks to be eliminated so that any mistakes they make or misfortunes they suffer are comparatively little ones.

    The same thing could be said for certain commenters here. This seems to be a fairly generic feature of people today (forever?).

  • Bubba Jones||

    Spoiler alert. It is captain Beckett now.

  • tarran||

    Shit... I just outed myself as someone who stopped watching after season 3, didn't I

  • Ron||

    proggies are more frightened by mass shooting because when they are not in their gated communities they are in gun free zones so they are the most vulnerable

  • Lee G||

    Proggies need a narrative, because without it, they can't get a major case of feelies going in their audience.

    Right now, that narrative is "mass shootings" and they will try to shoehorn everything bad into that little box.

    The right does it as well.

  • Jesse Walker||

    Why are "mass shootings" any more important than homicide totals?

    I think ultimately people say "mass shooting" when they mean "a shooting someplace where I'd expect to feel safe." Of course there isn't any good way to measure that, so people look for different stand-ins. That's part of the problem with the Mother Jones list—they make various exceptions to their ground rules to include the crimes that "feel" right, but when you mix inconsistency with statistical rarity you're just asking for trouble.

  • GILMORE™||

    "I think ultimately people say "mass shooting" when they mean "a shooting someplace where I'd expect to feel safe."

    That's probably true, and probably the impression they're trying to convey by touting the number of these incidents.

    However if you look at the actual incidents that make up the vast majority of the "Mass Shootings" in that tracker... most are 'drive-by spray & pray'-gunfire into crowds of people... mostly in the worst-neighborhoods of the most criminal cities in America.

    Not exactly "the planned parenthood clinic at the mall" or "your local health services center" or "church"

    for example.... the term "Block Party" seem to repeat itself over and over again in the linked-citations..

    e.g. Philly, Detroit...

  • GILMORE™||

  • GILMORE™||

    ...Tulsa, St Louis...

  • GILMORE™||

    ...Memphis, Compton...

    ...I feel like I need a "Land of 1000 Shootings" party-dance-number to go with it.

  • kinnath||

    Isn't this a Huey Lewis song?

  • Lee G||

    I believe it is The Heart of Lock N' Load

  • GILMORE™||

    Ahh, the "Japan only" version of their song.

  • Just say Nikki||

    I think ultimately people say "mass shooting" when they mean "a shooting someplace where I'd expect to feel safe."

    Yeah. It's freaky like serial killers are freaky. You can have no "risk factors" for being murdered and still get killed.

    I think this is also why so many of the tweets and stuff about this tend to say things like "society has accepted that living in the US is like a lottery for life and death" or some nonsense.

  • Lee G||

    Last I checked, the simple act of living is an everyday lottery for life and death.

  • CZmacure||

    "It's freaky like serial killers are freaky. You can have no "risk factors" for being murdered and still get killed."

    I've always presumed that serial killers prefer to kill people no one will miss, because they are on a spectrum of compulsive, amoral behavior but are not inhuman monsters driven to commit craven obvious crimes on statistical randoms because they get off on abstract ideals of fairness.

    tl;dr - serial killers probably kill a lot more prostitutes and transients than "randoms"?

    (a short wiki search... "Joel Rifkin confessed to killing 17 sex workers in the New York area between 1989 and 1993, without there having been a missing persons report filed on any of the women during that time.")

  • Lorenzo Zoil||

    Because Australia was able to use a mass shooting as a wedge issue to ban guns.

  • Zeb||

    And the UK and probably a bunch of other places.

  • JWatts||

    The UK used the fear of a Communist uprising hanging the aristocracy from lamp posts to ban guns.

  • Not okay||

    Because the majority of shootings are of no threat to people not involved in inner city drug and gang violence and America knows it. So they need to convince voters who are not in that demographic they are in danger and must ban their neighbor from owning a glock because he may be a "mass shooter."

    Happens all the time, except it's actually quite rare.

  • Bubba Jones||

    So the answer is that progs are racist?

  • Not okay||

    Maybe, but that wasn't really the point I was making. People generally are more concerned about threats affecting themselves and people they know. And most voters are not in a demographic that has a high probability of gun violence so they are trying to pretend they are.

  • Win Bear||

    Progressives have always been racist. Who do you think were the prime movers behind segregation and eugenics?

  • lawnerd||

    This. This is the essence of liberal hatred for guns and their bizarre anti-gun arguments.

  • Rt. Hon. Judge Woodrow Chipper||

    But does either method count shootings in which the police were the only ones firing? Or, as I suspect, are these more common occurrences completely ignored?

  • LynchPin1477||

    Yesterday, someone I know, who is an awesome person, said that as many people die in the US in 36 hours from "random bullets" as died in Paris.

    That would be 47,000 people per year from "random bullets" alone. It was an off the cuff comment, one probably heard somewhere else, but in 15 seconds I could tell that it had to be off by AT LEAST an order of magnitude to even be plausible.

  • BearOdinson||

    Well 93% of all statistics are made up, so.....

  • GILMORE™||

    "as long as readers understand what precisely each one describes"

    Given that the news media and twitterati are perfectly happy to mendaciously conflate "Shootings" with "Mass murders", i think this is a naive expectation.

  • Lee G||

    Is that an ASSAULT WEAPON in your pocket, or are you just happy to see me?

  • Certified Public Asshat||

    And as we saw yesterday, we now have ASSAULT CLOTHING!!11!! to worry about.

  • AlmightyJB||

    Nobody NEEDS to wear camouflage or black. If you ban black then you better ban white.

  • Jesse Walker||

    i think this is a naive expectation

    I didn't say I expected it.

  • GILMORE™||

    Touche, you magnificent bastard.

    I've myself recently tried pointing out the 20year decline in gun-violence ...(tending to refer to the BJS stats for both 'firearm homicides' and 'nonfatal fiream violence')...

    ...and the most-common retort is a combination of =

    1 = "You think everything is *fine* then?? You just want to DO NOTHING??" (huff puff stamp feet) NOTHING???!!


    2 = ""The US is still 10X more violent than X!!!"" (cherry picking ethnic/economically homogenous EU countries with low firearm violence)


    3 = "The only reason those homicide numbers have declined is because of better trauma sugery!"

  • Gray Ghost||

    Are there studies that examine your point #3, Gilmore? Because I tend to agree with that one. First Responder care/life flight/Trauma surgery has improved outcomes tremendously. No small thanks to our ongoing traumatic injury laboratory in the Middle East.

    But yeah, if these rates were in the late 80s/early 90s, we'd think we were dreaming.

  • ||

    Gray Ghost -Actually, yes; all forms of violent crime are down as well. If shootings were as common as ever, just being transformed from homicide into non-fatal crimes, we wouldn't see that fall.

  • LynchPin1477||

    I was thinking about this the other night, and the honest way to present the data would be per year, binned by both number of people killed and number of people injured, with bin sizes of 1 person. That way you don't have to arbitrarily define "mass shooting".

    But really, is it actually worse if someone dies in a high-profile mass shooting vs low profile gang violence or a shooting involving one person and an acquaintance? The answer is obviously "yes" in terms of psychological impact on the average person, but push anyone on it and the answer will probably be no. So just look at total number of deaths. Unless of course you want to create hysteria to push an agenda...

  • Lee G||

    Mass shootings are self-propagating events. Each one creates a lower threshold for the next event as the example is set yet again for some looney who needs a vehicle for their anger and desires the fame associated with it.

    So, in a perverse way, by paying more attention to and being even more hysterical about these shootings, we increase the likelihood they will happen again.

  • Sidd Finch v2.01||

    But really, is it actually worse if someone dies in a high-profile mass shooting vs low profile gang violence or a shooting involving one person and an acquaintance? The answer is obviously "yes" in terms of psychological impact on the average person, but push anyone on it and the answer will probably be no.

    I think you'd have to push the average person really hard towards a woodchipper to get that answer.

  • Just say Nikki||

    But really, is it actually worse if someone dies in a high-profile mass shooting vs low profile gang violence or a shooting involving one person and an acquaintance? The answer is obviously "yes" in terms of psychological impact on the average person, but push anyone on it and the answer will probably be no.

    Ha. But then they might have to, like, legalize drugs and prostitution instead of illegalizing guns!

  • Zeb||

    The psychological impact of someone you don't know dying in a mass shooting is certainly greater than low profile gang killing would be. I'm not sure that if it were someone I know personally I would a terribly different reaction. No one I know has ever been murdered, so it's hard to say.

  • kinnath||

    Liberals don't give a shit about the poor and downtrodden that get killed in random street violence, the criminal elements that kill each other, or the mentally-ill/drug-addled dude that is executed by the police.

    Liberals only care about "good" people killed in nice places (typically frequented by liberals) by a lone wacko with a gun.

  • Akira||


    If they truly cared about murder victims, they'd be focusing their efforts on Chicago and Baltimore. But those are already Team Blue dominions with strict gun laws, so they don't give a shit.

  • AlmightyJB||

    It's just a pretense no ban guns.

  • AlmightyJB||

    To. God,I can't wait until I can upgrade this piece of shit.

  • AlmightyJB||

    I don't see how anyone not in love with totalitarianism with more than a 4th grade education in history could think it is a good idea for only the government to have guns.

  • Curt||

    Denier! Why do you hate science?

    They found some science that backs their viewpoint. Therefore, all other science that disagrees is wrong and created by corporate cronies that are backed by the NRA and the Kochs and Bush and Trump and Banks and Oil Industry and Big Tobacco and militias and religion and the KKK and ...

  • ||

    Lies, damned lies and statistics.

    NO. You can't have my guns.

  • Rockabilly||

    This is my statistic.

    Amendment II

    A well regulated militia, being necessary to the security of a free state, the right of the people to keep and bear arms, shall not be infringed.

  • Alan@.4||

    Would a rose by another name truly smell as sweet? Who knows, but it remains, as Disraeli offered, "While figures might not lie, liars figure", an admonition that applies to this Gun Control business, with a vengeance.

  • Dallas H.||

    Jesse, even the description you provide for the mass shooting tracker is narrower than what they use. The criteria they use (at BEST) is 1 person shot and a total of 4 people injured via any means possible.

    For example, #111 this year is a cop shooting a guy on a domestic violence call where 1 cop is hit with a taser, another has cuts on his face, and the wife has "injuries."

    This is what counts as one of the "355 mass shootings" this year.

  • Dallas H.||

    There is also a decent audit of every case (including ones that are pellet guns or occurred 2 weeks apart or unrelated incidents on the same night or car accidents) here: http://www.thetruthaboutguns.c.....out-facts/

  • Sevo||

    Thx, DH. Both links are now where I can find them for the next 'five million people a year are...........!'

  • Dallas H.||

    No problem. I posted some of this a few times today, but I'm usually slow getting here and threads are dead and no one sees them. Glad someone did.

  • mrvco||

    So..... mass shootings have increased since Obama became president?

  • Ron||

    its a crowd issue if a person is alone in their own home they feel safe but when they are in a crowd say at a stadium or other big function whether it be an earthquake or mass shooting the ability to flee and protect oneself is limited. Of course thats why gatherings are targeted your trapped like cattle at the slaughter house.

  • Real American||

    you mean leftists are peddling misinformation based on faulty statistics created by activists with a motive to make it seem like the problem is greater than it really is so they can more easily promote their agenda and policy goals?

  • CPADave71||

    This is part of a larger problem. You remember the phrase "you're entitled to your own opinion, but not to your own facts"? That's dead. Everyone has their own facts, their own statistics, their own studies carefully designed to produce a result consistent with the intended narrative. The average person has no ability to discern from the noise what the actual situation is. This applies to mass shootings, climate change, immigration, welfare, etc. Science is dead. Journalism is dead. All that matters is advocacy and how you feel. The facts can always be bullied into compliance.


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