Ambiguity and legal compliance

• Published date: 01 November 2021
• Author: Timothy C. Barnum,Daniel S. Nagin
• Date: 01 November 2021
• DOI: http://doi.org/10.1111/1745-9133.12565

DOI: ./- .

ORIGINAL ARTICLE

Ambiguity and legal compliance

Timothy C. Barnum1Daniel S. Nagin2

Department of Criminology, Max Planck

Institute for the Study of Crime, Security

and Law, Freiburg im Breisgau, Germany

Heinz College, Carnegie Mellon

University, Pittsburgh, Pennsylvania, USA

Correspondence

TimothyC. Barnum, Department of Crim-

inology,Max Planck Institute for the Study

ofCrime, Security and Law, Günterstal-

straße,  Freiburg im Breisgau,

Germany.

Email:t.barnum@csl.mpg.de

Research Summary: This study examines the inde-

pendent and joint effect of ambiguity and perceived

certainty of apprehension on law-breaking decision-

making. Data come from a survey of experienced drivers

(N=) who viewed videos depicting a car speeding

on an interstate highway under experimentally manip-

ulated circumstances. The sampled drivers were gen-

erally ambiguity averse, opting to reduce speeding as

ambiguity about the perceived certainty of apprehen-

sion increased. However,perceived ambiguity interacted

with perceived certainty such that increases in ambigu-

ity increased the deterrent effect of ambiguity for low

certainty probabilities and decreased the effect for high

probabilities.

Policy Implications: Ambiguity may serve as a valu-

able tool for increasing the efficacy of crime-prevention

strategies, especially for crimes with naturally low lev-

els of risk. However, researchers should think carefully

about the effects of ambiguity when analyzing the effi-

cacy of certainty-based policies because the injection of

ambiguity can both increase and decrease legal compli-

ance. Also, discussed are the implications for a key func-

tion of policing—traffic safety.

KEYWORDS

ambiguity aversion, ambiguity seeking, deterrence, idiosyncrati-

cally coherent risk perceptions

This is an open access article under the terms of the Creative Commons AttributionLicense, which permits use, distribution and reproduc-

tion in any medium, provided the original work is properly cited.

©  The Authors. Criminology & Public Policypublished by Wiley Periodicals LLC on behalf of American Society of Criminology.

Criminology & Public Policy. ;:–. wileyonlinelibrary.com/journal/capp 621

622 BARNUM  NAGIN

Nearly three centuries ago, Beccaria () postulated that the certainty of punishment is a more

effective deterrent than the severity of the ensuing punishment. Decades of perceptual deterrence

research have consistently confirmed Beccaria’s postulate (e.g., Apel & Nagin, ;Nagin,;

Paternoster, ). This evidence has motivated a range of crime prevention policies aimed at

increasing the certainty of detection, such as hot spot policing (Braga & Apel, ;MacDonald

et al., ; Rosenfeld et al., ), which have consistently been demonstrated tobe effective. By

preventing crime from occurring in the first place, certainty-based prevention strategies have the

benefit of averting not only the social cost of crime but also the social cost of punishment.

Sherman (), however, interjected a caution that remains valid in contemporary United

States as it was  years ago: “in modern America there is too much crime and too little law

enforcement to make punishment very certain” (p. ). To this point, Sherman () and, subse-

quently, Nagin () theorized that law-breaking behavior could be further deterred by increas-

ing the level of equivocation or ambiguity about the likelihood of sanction certainty.For example,

Sherman (, p. ) suggested that by increasing police presence unpredictably,ambiguity would

be increased without sacrificing certainty averaged over time and across place.

The hypothesis that an aversion to ambiguity might be a deterrent independent of sanction cer-

tainty originates with what is now referred to as the “Ellsberg Paradox” (Ellsberg, ). Stripped

to its essentials, the Ellsberg Paradox is that people prefer simple gambles compared to com-

pound gambles with equivalent expectedvalue. Compound gambles are a form of decision making

under uncertainty in which there is not a single probability specifying the chances of an outcome.

Instead, there is a distribution of probabilities each with its own probability of occurring. By way

of example, consider the following simple and compound gambles with equal expected values.

In the case of the simple gamble, you are presented with an urn that conceals  red and  blue

balls. You win $ if a redball is chosen but lose $ if a blue ball is chosen. The expected value of

this simple gamble is $ ( =. ×$ – . ×$). In the compound version of the gamble, you are

told that the urn conceals between  and  red and blue balls and all  possible mixtures of

red and blue balls are equally likely.If unknown to you there are no red balls, then you are certain

to lose $. On the other hand, if the urn is all red balls, you are certain to win $. Thus, for each

 possible mixtures of red and blue balls the expected value for that simple gamble ranges from

–$ to +$. Because each possible mixture is equally likely, the expect value of the compound

gamble is $, the same as the expected value for the simple gamble where it is known that the

urn contains  red ball and  blue balls. Yetexperimental evidence overwhelmingly shows that

people prefer the simple gamble (even if they must pay for that option; see Becker & Brownson,

).

To date, however, evidence on the relationship between ambiguity and decision making pri-

marily comes from laboratory-based experimentsinvolving choices between differently structured

gambles. By contrast, crime is a real-world phenomenon in which would-be offenders must con-

sider benefits and/or costs that generally are not denominated in monetary terms (e.g., exact-

ing revenge, arrest, confinement, stigma, etc.). Moreover, as developed below and also in prior

research, ambiguity in some circumstances can increase deterrence as suggested by the Ells-

berg Paradox, but, in other circumstances, evidence and theory suggests ambiguity may actually

“diminish” it (Ellsberg, ).Consequently, it remains unclear how and to what extent ambiguity

influences the decision to take advantage of real-life offending opportunities.

This paper extends the nascent criminology literature on ambiguity by generalizing a model of

idiosyncratically coherent decision making set out in Barnum et al. () to account for the joint

effect of perceived certainty of apprehension and ambiguity in law-breaking decisions. In short,

this model describes two separate but interrelated components that contribute to the formation of