The Relationship between Driver Aggression behavior, Violence, and Vengeance

Abstract

A distinction is made between mild driver aggression behavior and driver violence as unique constructs that differ mainly in frequency of occurrence and severity of outcome.  Drivers completed questionnaires assessing the likelihood of engaging in mild driver aggression behavior, the frequency of past driver violence, driving vengeance, and willful violations.  Violence was predicted by the interaction of mild aggression behavior and vengeance, such that violence was greater among aggressive drivers, but only for those with elevated levels of vengeance. Driver violence was also predicted by the interaction of mild aggression behavior and violations.  Specifically, violence was greater among aggressive drivers reporting traffic violations.  The present findings suggest that mild driver aggression behavior and driver violence are linked within a small group of drivers that hold other dangerous driving attitudes and behaviors as part of their typical driving repertoire.

 

 

 

Introduction

While there is no universal operationalization of driver aggression behavior, historically, aggression behavior has been viewed as any behavior that is intentionally harmful (see Aronson, 1980; Baron, 1977; Berkowitz, 1984; Buss, 1961; Geen, 1995; Goranson, 1970).  Following this model, driver aggression behavior has been defined as any behavior intended to physically, psychologically, or emotionally, harm another within the driving environment, including drivers, passengers, and pedestrians (Hauber, 1980; Hennessy & Wiesenthal, 1999).  In contrast, the public perception of aggressive driving generally includes any risky or dangerous driving behavior regardless of harmful intent, such as speeding, weaving through traffic, running red lights, and using the shoulder to pass (Lonero, 2000).  According to Hennessy (1999a), the latter may be more accurately defined as assertive driving, involving time urgent and self oriented actions that can be dangerous and illegal, but lacking the harmful intent characteristic of aggression behavior.

While both aggression behavior and assertiveness pose a legitimate threat to motorists, there is growing support for the notion that they are distinct categories of driving behavior.  For example, James and Nahl (2000) have suggested that a motorist’s emotional impairment can lead to specific types of actions considered by observers to be “aggressive”.  Impatience and inattention may produce risky or assertive actions that comprise the lay notion of aggression behavior (e.g. speeding, advancing through red lights, and weaving through lanes), while power struggles yield harmful actions similar to the psychological model of aggression behavior (e.g. tailgating to punish another driver, swearing, and yelling).  Further, Lawton, Parker, Manstead, and Stradling (1997) have argued that interpersonal aggression behavior, involving acts of mild aggression behavior toward other drivers, are distinguished from highway code violations, such as speeding and running red lights (see also Parker, Lajunen, & Stradling, 1998; Stradling & Meadows, 2000).  Finally, Tasca (2000) noted that risky actions, including weaving, using the shoulder to pass, and running stop signs, should not be equated with displays of hostility, such as horn honking, making obscene gestures, and yelling at other drivers.

Hennessy (1999a) has also differentiated mild driver aggression behavior (e.g. horn honking, swearing, or hand gestures) from driver violence (e.g. fighting, shooting, or purposeful contact).  While both involve actions intended to harm others, they differ mainly in frequency and severity.  Mild aggression behavior is typically more common, but the immediate outcome is less severe than with violence.  Novaco (1991) has raised legitimate concerns over the predominant use of milder actions (i.e., horn honking) to operationally define driver aggression behavior.  Due to their limited severity, they generally represent minimal immediate threat, and are of less concern to drivers than violent behaviors.  The enduring danger in mild driver aggression behavior may come from its potential for escalation to more frequent and severe forms of driver aggression behavior (Novaco, 1991).  According to Novaco (1991) drivers that frequently engage in horn honking, for example, are more likely to report using obscene gestures, yelling, or tailgating other drivers.  The frequency of mild aggression behavior has also been found to increase under frustrating driving conditions (Hennessy & Wiesenthal, 1999), especially among highly stressed drivers (Hennessy & Wiesenthal, 2000).  Further, Hennessy (1999a) found that drivers more likely to engage in mild aggression behavior, were also more prone to report past acts of driver violence.

Driving Vengeance: A Link Between Aggression behavior and Violence

Hennessy (1999b) has suggested that mild aggression behavior may be more likely to escalate to violence among drivers holding vengeful attitudes.  Driving vengeance has been defined as the purposeful infliction of harm, including physical pain, emotional harm, humiliation and annoyance, on other roadway users in response to a perceived injustice (Gibson & Wiesenthal, 1996; Wiesenthal, Hennessy, & Gibson, 2000).  Vengeance typically involves extreme and often dangerous actions in response to seemingly minor infractions (Daly & Wilson, 1988; Stuckless & Goranson, 1992).  The objective of vengeance is typically to exert power and control over a rival or to provide relief from physical and emotional discomfort caused by the target of revenge (Black, 1983; Cramerus, 1990; Daly & Wilson, 1988; Lane, Hull, & Foehrenbach, 1991; Stuckless & Goranson, 1992).  Individuals holding a vengeful attitude are more prone to overreact to minor infractions and experience anger or irrational thoughts (Stuckless & Goranson, 1992; Gibson & Wiesenthal, 1996), which can further heighten the likelihood of aggressive or violent behaviors (Deffenbacher, Oetting, & Lynch, 1994; Stuckless, Ford, & Vitelli, 1995).

Vengeful drivers have been found to display elevated levels of mild aggression behavior in both hypothetical and actual driving situations (Wiesenthal & Hennessy, 1999; Wiesenthal et al., 2000) and to report greater frequency of previous driver violence.  Further, anecdotal and media reports of roadway aggression behavior typically depict revenge motivated scenarios, in which one driver feels unjustly treated by another driver and responds in an aggressive manner (Hennessy, 1999b).  Often the aggressive actions are reciprocated between the two parties and, in more extreme cases, mild aggression behavior escalates to more extreme acts of violence, with destructive, harmful, or fatal outcomes.

Willful Violations and Driver Aggression behavior

Another factor that might facilitate the escalation of mild driver aggression behavior to violence is the willingness to commit traffic violations.  Violations have been defined as deliberate defiance of safe driving patterns and traffic rules (Reason, Manstead, Stradling, Baxter, & Campbell, 1990).  Such actions are in contrast to errors and minor lapses, which can also lead to negative consequences, but are not deliberate infractions (Parker, Reason, Manstead, & Stradling, 1995b). Driving performance research has demonstrated that willful violations are more likely to lead to traffic collisions than errors or minor lapses (Evans, 1991; Parker et al., 1995b; Parker, West, Stradling, & Manstead, 1995c; Simon & Corbett, 1996).

While many drivers sporadically violate driving rules, there are some that maintain such actions as part of their typical driving behavior pattern (Hennessy, 1999a; Labiale, 1988; Reason et al., 1990).  These violations pose a danger to the driver and surrounding motorists, particularly in relation to their greater probability for producing accidents.  Similarly, Hennessy (1999a) found that violent driving behaviors were more prevalent among drivers who received greater numbers of demerit points (defined as sanctions issued for past traffic offences).  Those who choose to chronically violate driving rules may be more accepting of their own risky or dangerous driving practices, which may become ingrained as part of their typical driving behavior repertoire (Hennessy, 1999b; Reason et al., 1990).  As a result, it is possible that drivers willing to commit more traffic violations may also be more willing to tolerate the escalation of mild aggression behavior to more extreme and dangerous acts of driver violence.

Hypotheses

1. Driver violence will be predicted by the interaction of mild driver aggression behavior and driving vengeance. Among highly aggressive drivers, driver violence will be greater for those that also report elevated vengeance.
2. Driver violence will be predicted by the interaction of mild driver aggression behavior and violations. Violence will be greater for drivers that report elevated aggression behavior, but only in combination with high levels of willful traffic violations.

Method

Participants

The present study included 130 female and 74 male participants from the student and employee populations of Zayed University, as well as from the general Metropolitan UAE population.  Fifty-three participants were recruited from the undergraduate research participant pool at Zayed University, which consisted of first year undergraduate psychology students, who received one experimental credit for their involvement.  All others were obtained as voluntary participants through posted signs, personal contact, and snowball recruiting.

All participants were regular daily commuters in the Metropolitan UAE area.  A minimum of three years driving experience was required, with an average of 9.6 years (M=7.73 for females and M=12.82 for males).  Their ages ranged from 19-67 years, with an average of 27.0 years (M=25.50 for females and M=59.59 for males).  The average driving time ranged from 20 to 300 minutes per day, with an average of 94.5 minutes per day (M=94.90 for females and M=93.71 for males).

Measures

1. The Driving Vengeance Questionnaire (DVQ) (Wiesenthal et al., 2000). The DVQ was developed to evaluate a general susceptibility toward vengeful driving reactions.  Items represented common driving situations in which a participant might be irritated, or feel unjustly treated by another driver.  Participants were required to select a response from a series of four options involving decreasing levels of aggression behavior.  Response alternatives ranged from displays of extreme aggression behavior (e.g., forcing the other vehicle off the road) to nonaggressive reactions (e.g., do nothing).  Scoring consisted of assigning a rank to each item based on the level of aggression behavior involved in the chosen response option.  The first, and most extreme, option was assigned a rank of 4, while subsequent options, which decreased in their level of aggression behavior, were assigned ranks of 3, 2, and 1 respectively.  All items also included an open ended response option, to which participants could indicate an alternate response to those provided.  All alternate responses were independently rated as to their level of aggressiveness in relation to the options provided for that item.  For example, those deemed equivalent in aggression behavior to the most aggressive option for that item were given a rank of 4, while those considered equivalent to the nonaggressive option were given a rank of 1.  A vengeance score was calculated as the sum of all individual item ratings with higher scores indicating a more vengeful driving attitude.  The DVQ has been a reliable measure of vengeful driving attitudes (alpha=0.83), and predicts the likelihood of mild driver aggression behavior and violence (Hennessy & Wiesenthal, in press; Wiesenthal et al., 2000).

2. Self Report Driver Aggression behavior Questionnaire. The Self Report Driver Aggression behavior Questionnaire was developed to evaluate the likelihood of engaging in mild aggressive behaviors while driving (Hennessy, 1995; Hennessy & Wiesenthal, 1997, 1999, in press).  Aggressive items included horn honking out of frustration, purposeful tailgating, swearing/yelling, using hand gestures, and flashing high beams out of frustration.  Responses ranged from 0=“not at all” to 5=“nearly all the time”, indicating how frequently they generally engage in each item when driving.  An aggregate driver aggression behavior score was calculated as the mean response to the five individual items.  Higher scores indicated a greater likelihood of engaging in mild aggressive driving behaviors.

3. Violent Driving Questionnaire. The Violent Driving Questionnaire was designed to evaluate the frequency of initiating previous acts of violent driving behavior (Hennessy & Wiesenthal, in press). Items included physical roadside confrontations, chasing other vehicles, throwing objects at other vehicles, drive-by shootings, purposeful contact with another vehicle, verbal roadside confrontations, and vandalizing another vehicle.  Participants were asked to indicate the frequency of previously initiating each of the violent driving behaviors. An aggregate violence score was calculated as the mean response to the individual violence items. Higher scores indicated a greater frequency of past acts of driver violence.  Confidentiality of all responses was stressed prior to item presentation.

4. 4. Driving Behavior Questionnaire–Violation Subscale (DBQ). The DBQ (Parker et al., 1995b) has been developed as a self report measure of the frequency of violations, lapses, and errors.  Violations represent deliberate deviation from safe vehicle operation, while lapses characterize unwitting deviations from safe vehicle operation, errors being a departure from planned driving actions.  The present study used only the violation subscale, in which participants were asked to indicate the extent that they generally engaged in various traffic violations.  Responses ranged from 0=“never”, to 5=“nearly all the time”.  Scoring consisted of the mean response to the individual items.  Higher scores indicated a greater likelihood of committing willful traffic violations. The DBQ–Violation subscale has been found to have high reliability, with an alpha of 0.84 (Hennessy, 1999a) and a test-retest reliability of 0.81 (Parker et al., 1995b).

Procedure

Participants completed the Driving Vengeance Questionnaire (DVQ), Self Report Driver Aggression behavior Questionnaire, Violent Driving Questionnaire, and Driving Behavior Questionnaire (DBQ)—Violations subscale.  Due to the sensitive nature of the present driving measures, all questionnaires were completed anonymously with instructions emphasizing that all responses would be held in strict confidence.

Results

Intercorrelations, means, standard deviations and alpha reliabilities for the Driving Vengeance Questionnaire (DVQ), Driver Aggression behavior Questionnaire, Violent Driving Questionnaire, and Driving Behavior Questionnaire (DBQ) appear in Table 1.

Table 1.  Intercorrelations, Means, Standard Deviations, and Alpha Reliabilities for Driver Vengeance (DVQ), Driver Aggression behavior, Driving, Driver, Violations (DBQ), Age, and Gender

1

2

3

4

5

6

1.   Driving Vengeance (DVQ)

—

—

—

—

—

—

2.   Driver Aggression behavior

.63*

—

—

—

—

—

3.   Violent Driving

.39*

.39*

—

—

—

—

4.   Violations (DBQ)

.56*

.62*

.50*

—

—

—

5.   Age

-.33*

-.28

-.14

-.29

—

—

6.   Gender

.19

.09

.22

.22

.17

—

Mean

55.23

1.84

1.43

0.96

27.00

—

SD

11.74

4.50

0.84

0.61

11.10

—

Minimum

31.0

0.0

0.0

0.0

19.0

—

Maximum

89.0

41.0

4.4

2.7

67.0

—

Cronbach alpha

.79

.79

.69

.75

—

—

Note: n=192; *p<.01

A hierarchical entry stepwise multiple regression was calculated to determine the predictors of driver violence.  The main effects included mild driver aggression behavior, driving vengeance, willful violations, driver age, and gender.  In addition, all cross product interactions were also generated.  On the first run, all main effects were entered forcibly and all interaction terms were added stepwise.  On the second run, all significant interactions from the first run, along with their constituent main effects, were entered forcibly, while all other significant main effects (i.e. those not part of interaction effects) were added stepwise.  This strategy has been reported in greater detail elsewhere (e.g. Hennessy, Wiesenthal, & Kohn, in press; Kohn & Macdonald, 1992a,b; Kohn, Gurevich, Pickering, & Macdonald, 1994).   Table 2 contains the final regression model for driver violence.

Table 2.  Significant Predictors of Driver Violence

Predictor

b

    t

Aggression behavior X Vengeance X Gender

-.0015

 

-3.44*

Aggression behavior X Violations

1.193

 

2.48*

Aggression behavior

-.438

 

-.591

Vengeance

.0029

 

.937

Violations

.741

 

.764

Gender

-1.45

 

-1.463

Intercept

.336

 

 

 

Note: R²=.347, F(6,186)=16.465, p<.01; * p<.01

Figure 1.  Driver Violence as a function of mild driver aggression and vengeance for male drivers.

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