When Do People Label Attackers as Terrorists versus Mentally Ill?
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Social Impact Policy Mar 1, 2018

When Do Peo­ple Label Attack­ers as Ter­ror­ists ver­sus Men­tal­ly Ill?

New research shows that people’s assump­tions go beyond stereotypes.

Terrorism vs. mental illness as a reason for violence

Yevgenia Nayberg

Based on the research of

Masi Noor

Nour Kteily

Birte Siem

Agostino Mazziotta

It is a sad­ly famil­iar sce­nario: a lone attack­er com­mits a hor­ren­dous act of vio­lence. In the imme­di­ate after­math, the motive is unclear. Yet many peo­ple are quick to con­clude he must be men­tal­ly ill; oth­ers just as quick­ly assume he is a terrorist. 

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Kellogg’s Nour Kteily want­ed to under­stand the psy­cho­log­i­cal under­pin­nings of this stark divide.

In a series of three exper­i­ments — two of which involved sur­vey­ing par­tic­i­pants imme­di­ate­ly fol­low­ing a vio­lent attack — Kteily and coau­thors con­clude that the dri­ving force for this divide goes beyond stereo­types about ter­ror­ists. Instead, peo­ple are dri­ven by a desire to pro­tect their own views of the world and of the groups with which they asso­ciate themselves. 

If a per­son who shares, say, our par­ti­san beliefs or reli­gion com­mits a heinous act, our instinct is to explain that away, Kteily says. Attribut­ing vio­lence to men­tal ill­ness is one way to do that when there is no obvi­ous motive. 

But, the research shows, even after a motive becomes clear, peo­ple are still inclined to find ways to dis­tance them­selves from an in-group perpetrator. 

There is a desire, con­scious or uncon­scious, to dis­tance your group from nasty behav­ior, a desire to pro­tect your cher­ished iden­ti­ty,” says Kteily, an assis­tant pro­fes­sor of man­age­ment and organizations. 

The con­se­quences of this phe­nom­e­non go beyond sim­ply rein­forc­ing one’s own beliefs. When par­tic­i­pants assumed a per­pe­tra­tor was men­tal­ly ill, they were more like­ly to endorse a lenient pun­ish­ment. The oppo­site was true when par­tic­i­pants deemed the per­pe­tra­tor a terrorist. 

Moti­vat­ed Rea­son­ing

The back­drop for these find­ings is our increas­ing­ly par­ti­san and polar­ized world.

We’re get­ting more ide­o­log­i­cal­ly divid­ed,” Kteily says. So under­stand­ing the process­es that lead to or that influ­ence how we process infor­ma­tion is incred­i­bly important.” 

Kteily and coau­thors, Masi Noor, of Keele Uni­ver­si­ty in the UK, and Birte Siem and Agosti­no Mazz­iot­ta, both of Fer­nUni­ver­sität in Ger­many, began with an estab­lished psy­cho­log­i­cal con­cept called moti­vat­ed reasoning. 

Peo­ple will fill in the blanks with things that con­firm their exist­ing beliefs.”

Peo­ple engage in moti­vat­ed rea­son­ing to lessen dis­com­fort with an idea. For exam­ple, par­ents gen­er­al­ly believe their chil­dren are good peo­ple. So when faced with the uncom­fort­able fact that their child start­ed a school­yard fight, par­ents may be moti­vat­ed to explain away that real­i­ty by insist­ing that the oth­er kid start­ed it. 

This moti­va­tion extends beyond our fam­i­ly to larg­er groups — both demo­graph­ic groups like race or reli­gion, and par­ti­san groups that we vol­un­tar­i­ly join. 

Men­tal Ill­ness ver­sus Ter­ror­ism

The researchers’ first two stud­ies test­ed whether people’s par­ti­san beliefs pre­dict­ed whether they would label a vio­lent attack­er as men­tal­ly ill or a terrorist. 

It is jar­ring when some­one from your group com­mits a vio­lent act, the researchers rea­soned. An easy way to pro­tect your pos­i­tive beliefs about your group is to blame the vio­lent behav­ior on men­tal ill­ness. After all, if peo­ple are not in con­trol of their fac­ul­ties, they — and by exten­sion the group you both belong to — bear less cul­pa­bil­i­ty for their actions. On the oth­er hand, if some­one from a dif­fer­ent group com­mits the same action, you will be more will­ing to attribute the vio­lence to terrorism. 

The first study was con­duct­ed on the day of the Brex­it vote in Britain in 2016. A week ear­li­er, a British man named Thomas Mair mur­dered Jo Cox, a Mem­ber of Par­lia­ment who was a strong sup­port­er of the Remain” cam­paign that advo­cat­ed stay­ing in the Euro­pean Union. 

The researchers quick­ly put togeth­er their study. They sur­veyed rough­ly 200 British par­tic­i­pants online about their par­ti­san feel­ings on the Brex­it vote and about Mair’s moti­va­tion in stab­bing Cox. 

Impor­tant­ly, on the day of the Brex­it vote, Mair’s motives remained unclear. 

Par­tic­i­pants who sup­port­ed the Leave” cam­paign, and thus could see them­selves being grouped with Mair if his moti­va­tions end­ed up being polit­i­cal, were more like­ly to say that Mair was men­tal­ly ill than a ter­ror­ist. Con­verse­ly, those who iden­ti­fied as Remain” sup­port­ers — and thus would be less like­ly to find them­selves in the same par­ti­san group as Mair — tend­ed to label him a terrorist. 

Any time there’s ambi­gu­i­ty about someone’s motives, that allows room for peo­ple to bring their own per­spec­tives to bear on it,” Kteily says. Peo­ple will fill in the blanks with things that con­firm their exist­ing beliefs.” 

A sec­ond study showed a sim­i­lar pat­tern. Ger­man par­tic­i­pants were sur­veyed imme­di­ate­ly after a Syr­i­an refugee injured 15 peo­ple at a Ger­man fes­ti­val in 2016. Par­tic­i­pants who iden­ti­fied them­selves as pro-immi­gra­tion were more like­ly to say the per­pe­tra­tor was men­tal­ly ill. Those who self-iden­ti­fied as anti-immi­gra­tion were more like­ly to call the refugee a terrorist. 

Dis­tanc­ing the Attack­er

Next, the researchers test­ed what hap­pens when a perpetrator’s motive is clear. If peo­ple can­not attribute vio­lent behav­ior to men­tal ill­ness, will they find oth­er ways to pro­tect their own beliefs and cher­ished social identities? 

These find­ings indi­cate that stereo­types are not the only force at work when some­one is labeled either men­tal­ly ill or a terrorist.

The researchers sur­veyed about 500 Amer­i­cans online. First, they assessed how strong­ly par­tic­i­pants iden­ti­fied them­selves with Amer­i­ca through ques­tions such as, Being Amer­i­can is an impor­tant part of how I see myself.” 

Next par­tic­i­pants read about Mr. A,” a col­lege stu­dent arrest­ed after bran­dish­ing a rifle and yelling at passers­by. Some par­tic­i­pants read that Mr. A had a his­to­ry of heavy involve­ment in polit­i­cal gath­er­ings; oth­ers read that he was bipo­lar; a third group got no infor­ma­tion about his background. 

Par­tic­i­pants were then asked ques­tions about Mr. A, includ­ing whether his par­ents were like­ly born in the U.S. and whether he was like­ly Chris­t­ian, Jew­ish, Mus­lim, or athe­ist. The researchers won­dered whether par­tic­i­pants would dis­tance them­selves from Mr. A by say­ing he had for­eign-born par­ents or assum­ing he belonged to a minor­i­ty reli­gion, which would allow them to pro­tect their own sense of American-ness. 

Yeah, maybe this per­son is Amer­i­can,” Kteily says of their moti­vat­ed rea­son­ing. But he isn’t real­ly Amer­i­can. He’s not real­ly one of us.” 

Indeed, those who read about Mr. A’s polit­i­cal activ­i­ties were more like­ly to dis­tance them­selves from him com­pared to those who thought he was men­tal­ly ill. 

But there was fur­ther nuance to this result: It occurred most clear­ly when par­tic­i­pants high­ly iden­ti­fied as Amer­i­can and there­fore pre­sum­ably cared more about pro­tect­ing the Amer­i­can iden­ti­ty. When par­tic­i­pants had a low lev­el of Amer­i­can iden­ti­fi­ca­tion, they did not dis­tance them­selves more from the polit­i­cal­ly moti­vat­ed Mr. A than from the men­tal­ly ill one. 

These find­ings also indi­cate that stereo­types are not the only force at work when some­one is labeled either men­tal­ly ill or a ter­ror­ist, Kteily explains. 

One could imag­ine that par­tic­i­pants labeled Mr. A a Mus­lim when they learned he was polit­i­cal­ly moti­vat­ed not because they want­ed to dis­tance him from their group, but because they stereo­typ­i­cal­ly asso­ci­at­ed Islam with polit­i­cal violence. 

How­ev­er, the find­ings sug­gest this was not the case. Par­tic­i­pants who strong­ly iden­ti­fied as Amer­i­can would pre­sum­ably not have been any more or less exposed to stereo­types of Mus­lims being ter­ror­ists than par­tic­i­pants who weak­ly iden­ti­fied as Amer­i­cans. Yet the results dif­fered between these two groups in how like­ly they were to assume Mr. A was Muslim. 

The results also high­light why ascrib­ing polit­i­cal ver­sus men­tal-health motives to vio­lent attack­ers mat­ters: par­tic­i­pants who believed Mr. A was polit­i­cal­ly moti­vat­ed advo­cat­ed for harsh­er pun­ish­ment than those who thought he was men­tal­ly ill. 

Grow­ing Par­ti­san­ship

This desire to pro­tect one’s own group may help explain how one person’s ter­ror­ist is another’s men­tal­ly trou­bled per­pe­tra­tor. But it does not make the dis­cus­sions around these events any eas­i­er, Kteily says — espe­cial­ly as we dig in deep­er and deep­er into our respec­tive par­ti­san camps. 

Kteily, who dis­cussed his research in the week after the Park­land, Flori­da school shoot­ing, ref­er­enced the heat­ed debates about gun con­trol that followed. 

Peo­ple are bring­ing to bear infor­ma­tion that fits pre­ex­ist­ing beliefs. That’s part of why the debate becomes so fraught,” he says. Any giv­en set of data can be chopped and served up dif­fer­ent­ly, and peo­ple do that in sys­tem­at­ic ways that align with their par­ti­san iden­ti­ty. We’re not unbi­ased con­sumers of infor­ma­tion. Rather, we go look­ing with­in infor­ma­tion to find what we already believe.”

Featured Faculty

Nour Kteily

Associate Professor of Management & Organizations

About the Writer

Emily Stone is the senior research editor at Kellogg Insight.

About the Research

Noor, Masi, Nour Kteily, Birte Siem, and Agostino Mazziotta. In press. “’Terrorist' or 'Mentally Ill': Motivated Biases Rooted in Partisanship Shape Attributions.” Social Psychological and Personality Science.

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