Six Things To Know About Mass Shootings In America

Six Things To Know About Mass Shootings In America
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America has experienced yet another mass shooting, this time at the Mandalay Bay Resort and Casino on the strip in Las Vegas, Nevada. It is reportedly the deadliest mass shooting in U.S. history.

As a criminologist, I have reviewed recent research in hopes of debunking some of the common misconceptions I hear creeping into discussions that spring up whenever a mass shooting occurs. Here’s some recent scholarship about mass shootings that should help you identify misinformation when you hear it.

#1: More guns don’t make you safer

A study I conducted on mass shootings indicated that this phenomenon is not limited to the United States.

Mass shootings also took place in 25 other wealthy nations between 1983 and 2013, but the number of mass shootings in the United States far surpasses that of any other country included in the study during the same period of time.

The U.S. had 78 mass shootings during that 30-year period.

The highest number of mass shootings experienced outside the United States was in Germany – where seven shootings occurred.

In the other 24 industrialized countries taken together, 41 mass shootings took place.

In other words, the U.S. had nearly double the number of mass shootings than all other 24 countries combined in the same 30-year period.

Another significant finding is that mass shootings and gun ownership rates are highly correlated. The higher the gun ownership rate, the more a country is susceptible to experiencing mass shooting incidents. This association remains high even when the number of incidents from the United States is withdrawn from the analysis.

Similar results have been found by the United Nations Office of Drugs and Crime, which states that countries with higher levels of firearm ownership also have higher firearm homicide rates.

My study also shows a strong correlation between mass shooting casualties and overall death by firearms rates. However, in this last analysis, the relation seems to be mainly driven by the very high number of deaths by firearms in the United States. The relation disappears when the United States is withdrawn from the analysis.

#2: Shootings are more frequent

A recent study published by the Harvard Injury Control Research Center shows that the frequency of mass shooting is increasing over time. The researchers measured the increase by calculating the time between the occurrence of mass shootings. According to the research, the days separating mass shooting occurrence went from on average 200 days during the period of 1983 to 2011 to 64 days since 2011.

What is most alarming with mass shootings is the fact that this increasing trend is moving in the opposite direction of overall intentional homicide rates in the U.S., which decreased by almost 50 percent since 1993 and in Europe where intentional homicides decreased by 40 percent between 2003 and 2013.

People run from the Route 91 Harvest country music festival after apparent gun fire was hear on October 1, 2017 in Las Vegas, Nevada. (Photo by David Becker/Getty Images)

#3: Restricting sales works

Due to the Second Amendment, the United States has permissive gun licensing laws. This is in contrast to most developed countries, which have restrictive laws.

According to a seminal work by criminologists George Newton and Franklin Zimring, permissive gun licensing laws refer to a system in which all but specially prohibited groups of persons can purchase a firearm. In such a system, an individual does not have to justify purchasing a weapon; rather, the licensing authority has the burden of proof to deny gun acquisition.

By contrast, restrictive gun licensing laws refer to a system in which individuals who want to purchase firearms must demonstrate to a licensing authority that they have valid reasons to get a gun – like using it on a shooting range or going hunting – and that they demonstrate “good character.”

The type of gun law adopted has important impacts. Countries with more restrictive gun licensing laws show fewer deaths by firearms and a lower gun ownership rate.

#4: Background checks work

In most restrictive background checks performed in developed countries, citizens are required to train for gun handling, obtain a license for hunting or provide proof of membership to a shooting range.

Individuals must prove that they do not belong to any “prohibited group,” such as the mentally ill, criminals, children or those at high risk of committing violent crime, such as individuals with a police record of threatening the life of another.

Here’s the bottom line. With these provisions, most U.S. active shooters would have been denied the purchase of a firearm.

#5: Not all mass shootings are terrorism

Journalists sometimes describe mass shooting as a form of domestic terrorism. This connection may be misleading.

There is no doubt that mass shootings are “terrifying” and “terrorize” the community where they have happened. However, not all active shooters involved in mass shooting have a political message or cause.

For example, the church shooting in Charleston, South Carolina in June 2015 was a hate crime but was not judged by the federal government to be a terrorist act.

The majority of active shooters are linked to mental health issues, bullying and disgruntled employees. Active shooters may be motivated by a variety of personal or political motivations, usually not aimed at weakening government legitimacy. Frequent motivations are revenge or a quest for power.

People dive for cover at Route 91 Harvest country music festival after apparent gun fire was heard on October 1, 2017 in Las Vegas, Nevada. (Photo by David Becker/Getty Images)

#6: Historical comparisons may be flawed

Beginning in 2008, the FBI used a narrow definition of mass shootings. They limited mass shootings to incidents where an individual – or in rare circumstances, more than one – “kills four or more people in a single incident (not including the shooter), typically in a single location.”

In 2013, the FBI changed its definition, moving away from “mass shootings” toward identifying an “active shooter” as “an individual actively engaged in killing or attempting to kill people in a confined and populated area.” This change means the agency now includes incidents in which fewer than four people die, but in which several are injured, like this 2014 shooting in New Orleans.

This change in definition impacted directly the number of cases included in studies and affected the comparability of studies conducted before and after 2013.

Some researchers on mass shooting, like Northeastern University criminologist James Alan Fox, have even incorporated in their studies several types of multiple homicides that cannot be defined as mass shooting: for instance, familicide (a form of domestic violence) and gang murders.

In the case of familicide, victims are exclusively family members and not random bystanders.

Gang murders are usually crime for profit or a punishment for rival gangs or a member of the gang who is an informer. Such homicides don’t belong in the analysis of mass shootings.

The ConversationEditor’s note: this piece was updated on Oct. 2, 2017. It was originally published on Dec. 3, 2015.

Frederic Lemieux, Professor of the Practice and Faculty Director of the Master’s in Applied Intelligence, Georgetown University

This article was originally published on The Conversation.


  • It’s raised every time there’s yet another mass shooting in the US, and is subsequently always ignored, but the country really needs some form of gun control.

    • Yeah, it was super apparent after Sandy Hook, if the deaths of little children didn’t have people protesting in the streets, nothing will. It was a sad day for so many reasons but mostly because it just proved your point. They literally love their guns and their gun rights more than actual kids.

  • The big thing is America (Mainly the right wing and Republicans) refuse to do anything to stop these mass shootings. They dont care that people and children die as long as they get to keep their guns.

    • The Gun Lobby is the most powerful in that country and they are in everyone’s pocket. Both Republicans and Democrats are reluctant to lose their donations, so this shit will not stop until a POTUS has enough backing and big enough balls to put a stop to it. In short, not gonna happen.

  • Another shooting and another article about gun control….avoiding the real problem. HEALTH CARE especially MENTAL Health!!! What do you think would happen if we take the guns away? Something worse. Do you think in ALL of these incidents the guns were LEGALLY obtained? We should take away cars as they cause more death than guns! Should there be BETTER gun control? ABSOLUTELY! Guns don’t kill.. people KILL people we need better Health care. Where is the data on mass murder in relation to explosives ?

    • Guns don’t kill.. people KILL peopleBullshit! People with guns, kill people! Stupid argument all round. Sure mental health is an issue, but if they aren’t able to get guns the problem is reduced incrementally.

      • Really…. could you not read between the lines? The gun is just a tool take it away and they will find something else and most likely something worse. Your idea of taking away guns wont stop the mass deaths. Just as drugs being illegal did nothing to resolve the Drug problem.

      • I will be Honest I did not own a gun until my Child wanted to join the military. i wanted him to have a understanding of them as really all people should. The are locked in a Safe and the ammunition is locked away also with a separate lock. My wife and I carry the only keys. I live in a state where you may carry an unconcealed gun or if you want to carry concealed you must take a test a get a permit. I do not carry a gun in either way.

        America represents the right to chose. I respect either choice and see mass shootings or deaths as what they really are someone who has gone over the edge mentally and we have failed to help them. The deaths of the innocent are horrible in any situation I truly pray for those victims and their family’s.

        • Because praying really ever does anything. Praying is just you virtue signalling so you can make yourself feel better. You want to know what people are actually doing to help? Donating blood. But no, you just instead sit inside your house and remain ignorant thinking its fine that people keep getting slaughtered by lunactics as long as you have your guns, but then its all good because you prayed to an imaginary god.

          America sure does represent the right to choose. America continues to choose to allow these things to happen and never do anything to prevent it. I mean for gods sake your NRA campaigned to make it illegal for the CDC to do any research at all into gun violence. Your own government lets these things happens. And then can look into why it happened and what you can do to stop it. Instead its all “DERRRNT TEKKKK AWERYYYYY MUUHHH GERRRRNNNS” meanwhile children lie dead on the floor because some lunatic went into a store and legally purchased a gun.

        • So you prayed for the victims, did you make a donation to their families to help pay for the funerals? Because unless you did, your prayers didn’t do squat! Why would you use your child’s decision to join the military, something that seems to be a right of passage these days for Yanks, to buy a weapon? don’t they teach them that in soldier school? At least be honest here, you bought the weapon because you wanted it.

      • Excuse me… I don’t lack in anything. No death does not justify any purchase. There were 1.25 million road deaths world wide so we should all stop buying cars right?

        • No, And what you just did there is a false equivalency.

          Let me put it to you this way. Had this guy not had access to those guns. 60 people would still be alive today.

          Justify to me why Ordinary citizens need to be able to purchase Military spec Assault rifles. Justify to me why just this week congress is going to pass legislation that makes it legal for consumers to buy Armour piercing rounds for “Sport”


          Continue being ignorant. At least australia does not have dead childrens blood on their hands. You have that. We dont have to worry about a lunatic taking a machine gun into a school. Next time you go to buy a gun or think about protecting them. Think about those children who were slaughtered at schools just so you could compensate for your tiny appendage.

          You defending these things is saying the slaughtering of children is fine as long as you get your guns. What a scummy person you are.

  • You ask “What do you think would happen if we take the guns away?”
    – We think that something like what happened here in Australia when we made tougher gun laws in the aftermath of a mass shooting that these sort of tragedies would almost be eliminated entirely instead of increasing to every second month as the article shows
    *you also ask “Do you think in ALL of these incidents the guns were LEGALLY obtained?”
    – more to the point do you think any of these guns were illegally obtained?? As the article points out with stricter gun laws none of these animals (offenders) would have been able to purchase their guns. and although the article was originally done in 2015 tougher laws would have obviously precluded this idiot from having more than 50 deadly weapons!
    * and “We should take away cars as they cause more death than guns!”
    -yep overall there probably are more deaths by cars than guns BUT… the majority are accidental not deliberate murders. Your comparison to even be remotely comparable you would need to include all gun deaths not just mass shootings ie individual murders, accidental shootings and suicides or limit the car death toll to deliberate killings which would leave gun deaths massively higher. Include those and you’ll find in the USA the death toll for each are a lot closer. Oh and in how many of these “deliberate” car deaths did the assailant go ‘awe my cars run out of petrol or too damaged to keep driving I’ll just jump in my other one here and keep killing?
    *oh and this favourite saying from the pro-gun lobby “Guns don’t kill.. people KILL people” yet again putting two things that aren’t comparable (oh and completely eliminating your own argument about cars having a higher death toll, makes as much sense to say Cars don’t kill.. people KILL people) and are in completely different categories comparing an inanimate object with a moving thinking person make more sense and is more accurate to say ‘Guns don’t kill.. people KILL people..and people with guns kill even more people’

  • Don’t get me wrong, I’m all for gun control, but I think data also needs to be represented as mass shootings per capita, not just guns per capita.

    I know I could do some of the maths myself, but failing to include such a measure skews the results.

    Taking France (1/5 of the population of the US) and Germany (1/4 of the population of the US), you get an equivalent of 30 shootings each if their populations were the same as the US.

    Now you can realistically correlate against gun ownership.

    Multiply by three to match the number of guns per capita in US, and you’ve got almost exactly the same number of gun deaths as in the US

    If that doesn’t show a 1 to 1 correlation between gun deaths and gun ownership, I don’t know what else does.

    • Looking at the data, France and Germany have 1 mass shooting per 11 million people. The US has one per 4 million people. This takes no account of casualties – only the events.

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