Do Speeding Tickets Reduce the Likelihood of Receiving Subsequent Speeding Tickets? A Longitudinal Study of Speeding Violators in Maryland

Objective. Speeding tickets are the most commonly used tool to deter speeders, yet little is known about how speeding citations affect individual drivers' behavior over time. This study examined the effects of being cited for speeding and types of legal consequences on drivers' subsequent speeding citations, which are an indicator of speeding behavior.

Methods. A cohort of 3,739,951 Maryland licensed drivers were identified and followed for one year. Drivers were categorized by whether or not they received a speeding citation in May 2002. Among those cited for speeding in May 2002, drivers were grouped by type of penalty (fines and points; probation before judgment [PBJ, which results in fines but no points]; or no legal consequences). The relative risks (RR) and 95 percent confidence intervals (CI) of receiving a speeding citation during follow-up were compared between drivers ticketed and not ticketed in May 2002, as well as among different penalty groups. Cox proportional hazards regression modeling was used to adjust for potential confounders, including age, gender, alcohol-impaired driving, and residence. Kaplan-Meier survival functions were used to examine timing of violations.

Results. Young drivers and male drivers were more likely to receive a speeding citation. Drivers who received a speeding citation in May 2002 had almost twice the risk of receiving a speeding citation during follow-up, compared with those not cited for speeding that month (RR 1.6, 95% CI 1.52–1.68). Overall legal consequences had no significant effect on the risk of receiving a repeat speeding citation relative to ticketed drivers who escaped those consequences (RR 0.98, 95% CI 0.84–1.15); however, stratified analyses showed a significant decrease in repeat citations among females (RR 0.75, 95% CI 0.63–0.90) and drivers who received PBJ (RR 0.81, 95% CI 0.67–0.96). Kaplan-Meier curves showed that the study group of speeders had a significantly shorter time between May 2002 until receipt of a speeding citation than controls. Among penalty groups, significantly shorter times until receipt of another citation were observed among drivers escaping consequences or receiving fines/points compared with drivers receiving fines/PBJ.

Conclusions. Drivers who receive speeding citations are at increased risk of receiving subsequent speeding citations, suggesting that speeding citations have limited effects on deterrence in the context of the current traffic enforcement system. When comparing different penalties, PBJ is associated with a reduced rate of recidivism more than stronger penalties; however, it is unclear whether the reduction primarily is attributable to the penalty itself or to characteristics of drivers receiving PBJ. Increasing drivers' perceptions that they are at risk of being caught speeding may improve the effectiveness of speeding law enforcement.

Keywords:

• Speeding
• Traffic Citations
• Alcohol-Impaired Driving
• Recidivism
• Traffic Enforcement
• Probation before Judgment

ACKNOWLEDGMENT

The authors thank the following colleagues at the University of Maryland at Baltimore: Timothy Kerns of the National Study Center for Trauma and Emergency Medical Systems for preparing extracts of data and providing advice on data manipulation; Patricia Langenberg of the Department of Epidemiology and Preventive Medicine for helpful suggestions regarding study design and statistical analyses; and Linda Kesselring of the Department of Surgery for providing editorial assistance. This study was conducted using data from the Maryland Crash Outcome and Data Evaluation System.

Notes

∗Chi-square P-value.

∗∗County groups based on citations per licensed driver residing in the county.

∗∗∗DUI/DWI: Driving under the influence of alcohol or driving while intoxicated.

∗Reference group.

∗∗Percentages within age and gender subgroups of the study and control groups.

∗∗∗Adjusted for age, gender, grouped county of residence, DUI/DWI citations during follow-up.

∗Reference group.

∗Chi-square P-value.

∗∗County groups based on citations per licensed driver residing in the county.

∗Adjusted for age, gender, grouped county of residence, subsequent DUI/DWI citations.