"Long before it's in the papers"
January 27, 2015


Darkness promotes dishonesty, researchers find

March 3, 2010
Courtesy of University of Toronto
and World Science staff

Dark­ness may en­cour­age dis­hones­ty by pro­mot­ing a feel­ing of im­pun­ity, some sci­en­tists say.

The ef­fect is rem­i­nis­cent of the words of Ralph Waldo Em­er­son, who wrote in 1860: “as gas­light is the best noc­tur­nal po­lice, so the uni­verse pro­tects it­self by pit­i­less pub­licity.” 

Psy­chol­o­gists had vol­un­teers go in­to well or dimly lit rooms and work on some puz­zles, grade them­selves, and award them­selves a spe­cif­ic sum of mon­ey based on the re­sult­s—all on the hon­or sys­tem.

Dark­ness wit­nessed great­er cheat­ing, the sci­en­tists not­ed, re­port­ing their find­ings in the re­search jour­nal Psy­cho­log­i­cal Sci­ence. Wear­ing dark sun­glass­es had si­m­i­lar ef­fects, they added.

The psy­chol­o­gists at the Uni­vers­ity of To­ron­to and the Uni­vers­ity of North Car­o­li­na at Chap­el Hill con­ducted three ex­pe­ri­ments. In the first, par­ti­ci­pants were placed in a dimly or well-lit room and giv­en a brown en­ve­lope that con­tained $10 along with an emp­ty white en­ve­lope. They were then asked to com­plete a work­sheet with 20 grids of num­bers, each con­sist­ing of 12 three-digit num­bers. 

The par­ti­ci­pants had five min­utes to find two num­bers in each grid that added up to 10. The re­search­ers left it up to the par­ti­ci­pants to score their own work. For each pair of num­bers in­den­ti­fied they could keep 50 cents. At the end, the par­ti­ci­pants were asked to leave the re­main­ing mon­ey in the en­ve­lope.

There was no dif­fer­ence in ac­tu­al per­for­mance, but par­ti­ci­pants in the slightly dim room cheated more, the re­search­ers found.

In the sec­ond ex­pe­ri­ment, some par­ti­ci­pants wore a pair of sun­glass­es and oth­ers wore clear glass­es while in­ter­act­ing with an os­ten­si­ble strang­er in a dif­fer­ent room. In real­ity par­ti­ci­pants in­ter­acted with an ex­pe­ri­menter. Each per­son had $6 to al­lo­cate be­tween him- or her­self and the re­cip­i­ent and could keep what he or she did­n’t of­fer. Par­ti­ci­pants wear­ing sun­glass­es were found to act more self­ishly by giv­ing sig­nif­i­cantly less than those wear­ing clear glass­es.

In the third ex­pe­ri­ment, the sci­en­tists rep­li­cat­ed the pre­vi­ous ex­pe­ri­ment and then meas­ured the ex­tent to which par­ti­ci­pants felt anon­y­mous dur­ing the ex­pe­ri­ment. Once again, those wear­ing sun­glass­es gave sig­nif­i­cantly less mon­ey and also re­ported feel­ing more anon­y­mous, the in­vest­i­ga­tors said.

Across all ex­pe­ri­ments, dark­ness had no bear­ing on ac­tu­al an­o­nym­ity, the psy­chol­o­gists noted. They sug­gest that the ex­perience of dark­ness may in­duce a sense of an­o­nym­ity dis­pro­por­tion­ate from ac­tu­al an­o­nym­ity of the situa­t­ion. 

“Imag­ine that a per­son alone in a closed room is de­cid­ing wheth­er to lie to a to­tal strang­er in an e­mail. Clear­ly, wheth­er the room is well-lit or not would not af­fect the per­son’s ac­tu­al lev­el of an­o­nym­ity. Nev­er­the­less, dark­ness may li­cense un­eth­i­cal be­hav­ior in such situa­t­ions,” said Chen-Bo Zhong of the Uni­vers­ity of To­ron­to, one of the re­search­ers.

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Darkness can conceal identity and promote a sense of impunity for moral transgressions, some scientists say. The effect is reminiscent of the words of Ralph Waldo Emerson, who wrote in 1860: “as gaslight is the best nocturnal police, so the universe protects itself by pitiless publicity.” Psychologists had volunteers go into well or dim ly lit rooms and work on some puzzles, grade themselves, and award themselves a specific sum of money based on the results—all on the honor system. Darkness witnessed greater cheating, the scientists noted, reporting their findings in the research journal Psychological Science. Wearing dark sunglasses had similar effects, they added. The psychologists at the University of Toronto and the University of North Carolina at Chapel Hill conducted three experiments. In the first, participants were placed in a dim ly or well-lit room and given a brown envelope that contained $10 along with an empty white envelope. They were then asked to complete a worksheet with 20 grids of numbers, each consisting of 12 three-digit numbers. The participants had five minutes to find two numbers in each grid that added up to 10. The researchers left it up to the participants to score their own work. For each pair of numbers indentified they could keep 50 cents. At the end, the participants were asked to leave the remaining money in the envelope. There was no difference in actual performance, but participants in the slight ly dim room cheated more, the researchers found. In the second experiment, some participants wore a pair of sunglasses and others wore clear glasses while interacting with an ostensible stranger in a different room. In reality participants interacted with an experimenter. Each person had $6 to allocate between him-or herself and the recipient and could keep what he or she didn’t offer. Participants wearing sunglasses were found to act more selfish ly by giving significant ly less than those wearing clear glasses. In the third experiment, the scientists replicated the previous experiment and then measured the extent to which participants felt anonymous during the experiment. Once again, those wearing sunglasses gave significant ly less money and furthermore, those wearing sunglasses reported feeling more anonymous during the study. Across all experiments, darkness had no bearing on actual anonymity, yet still increased un ethical behavior, the psychologists said. They suggest that the experience of darkness may induce a sense of anonymity disproportionate from actual anonymity of the situation. “Imagine that a person alone in a closed room is deciding whether to lie to a total stranger in an email. Clearly, whether the room is well-lit or not would not affect the person’s actual level of anonymity. Nevertheless, darkness may license un ethical behavior in such situations,” said Chen-Bo Zhong of the University of Toronto, one of the researchers.