An evaluation of Washington's driving while intoxicated law: Effect on drunk driving recidivism

The 1980 Washington driving while intoxicated (DWI) law was evaluated to determine its impact on the subsequent driving behavior of persons convicted of DWI. The major provisions of this law were mandatory jail sentences for conviction of DWI and a change in the definition of DWI. The law made it illegal per se for a person to drive with a blood alcohol level of .10% or more. The law was intended to reduce the drunk driving and accidents of individuals convicted of DWI as well as deter such behavior among the general driving population. The study assessed the deterrence effect of the law on convicted DWI offenders. It was found that individuals convicted under the provisions of this law had higher accident rates and drunk driving recidivism rates than individuals convicted under the previous law. These increases suggest that mandatory jail sentences may fail to deter subsequent acts of drunk driving. It was concluded that alternative legal sanctions for DWI (such as license suspensions or revocations) may be sufficiently stringent to produce both general and specific deterrence of drunk driving.     

Predictors of conviction and sentencing of DWI offenders in a New Mexico County

OBJECTIVE: To analyze predictors of conviction and dismissal of individuals charged with DWI, and predictors of the sentences of those who are convicted. METHODS: Data come from the Citation Tracking System of the State of New Mexico's Motor Vehicle Division and includes information on all individuals who were arrested for DWI in San Juan County between August 1994 and December 2000. Independent variables were: age, gender, race/ethnicity, waiver of right to an attorney, court of arraignment, year of arrest, BAC, and number of prior DWI arrests. Dependent variables were: (1) conviction or dismissal, (2) jail or no jail, (3) incarceration/treatment or not, (4) fine or no fine, (5) length of jail sentence, (6) waived right of attorney, and (7) magnitude of fine. Multiple linear and logistic regression was used in the analyses. RESULTS: Use of an attorney is associated with reduced likelihood of conviction and, if convicted, in reduced likelihood of jail sentence and reduced jail time, but greater likelihood and magnitude of a fine. Native Americans were more likely than Hispanics and non-Hispanic whites to waive their right to an attorney. Native Americans were most likely to be sentenced to the detention/treatment program. BAC and number of prior arrests were each positively associated with increased likelihood of conviction and more severe sentences. There is also substantial variability in severity of sentencing among courts. CONCLUSION: Likelihood of conviction and severity of sentences are both determined by extra-legal factors, resulting in inconsistent application of the law. This may in turn contribute to a lack of compliance with laws related to DWI.     

Variations in jail sentences and the probability of re-arrest for driving while intoxicated

OBJECTIVE: The probability of re-arrest for driving while intoxicated (DWI) is compared for four different groups of individuals classified by whether the individual was convicted and, if so, the type of sentence received. METHOD: Subsequent re-arrests for DWI were examined for all individuals whose index arrest for DWI had occurred between 1994 and 2001 in a county in New Mexico. The groups included (1) those convicted as a result of the index arrest and sentenced to a 28-day jail/treatment program (N (#)=(#) 2,703); (2) all those not convicted as a result of the index arrest (N = 709); (3) those who were convicted but not sentenced to jail (N = 1,047); and (4) those convicted and sentenced to jail (N = 1,290). RESULTS: Adjusting for covariates of BAC, number of prior arrests, ethnicity, age, and sex, the probability of not being re-arrested was greatest among those sentenced to the jail/treatment program (Group 1), next highest in the two groups convicted but not sentenced to jail/treatment (Groups 3 and 4), and lowest in the group that was not convicted (Group 2). Length of jail sentence among people convicted but not sentenced to the jail/treatment program was unrelated to the probability of re-arrest. CONCLUSION: Conviction for DWI, regardless of the sentence, appears to reduce the probability of re-arrest, and being sentenced to a multi-modal treatment/incarceration program further reduces the probability of re-arrest. However, the other types of sentences do not appear to differ in their impact on probability of re-arrest.     

A note on the effectiveness of the house-arrest alternative for motivating DWI offenders to install ignition interlocks

Introduction

The effectiveness of ignition interlocks at reducing drunk driving has been limited by the ability of driving-while-intoxicated (DWI) offenders to avoid court orders to install the devices.

Methods

In a pilot program in New Mexico, four Santa Fe County judges imposed home confinement (via electronic monitoring bracelets) on offenders who claimed to have no car or no intention to drive. Interlock installation rates for Santa Fe County were compared with all other counties in New Mexico over a 2-year program and 2-year post-program period.

Results

During the two program years, 70% of the drivers convicted of DWI in Santa Fe County installed interlocks, compared to only 17% in the other counties, but when the program was terminated, the Santa Fe installation rate fell by 18.8 percentage points.

Summary

Mandating the alternative sanction of house arrest led to the highest reported interlock installation rate for DWI offenders.

Impact on Industry

Impaired driving is a substantial expense to employers, particularly when it bars driving that interferes with employment. Interlocks provide a method of protecting the public while permitting the offender to drive sober. This study was directed at increasing interlock use by DWI offenders.     

Mandating interlocks for fully revoked offenders: the New Mexico experience

OBJECTIVE: In New Mexico, between July 1999 and December 2002, the installation of an ignition interlock was an optional judicial sanction for second and third driving-while-impaired (DWI) offenders. This is a study of the recidivism of 437 offenders who were convicted and installed interlocks for an average of 322 days during that period. METHODS: The comparison group was a stratified random sample (N = 12,554) of the 20,949 offenders who were convicted during the same period but did not install interlocks. DWI arrest and conviction data for all study participants were received from the Motor Vehicle Department's Citation Tracking System. RESULTS: Only 11 (2.5%) of the interlock offender group were rearrested for DWI while interlocks were installed, whereas 1,017 (8.1%) of the comparison group were rearrested during an equivalent 322-day period. Survival graphs and Cox proportional hazard regression analyses were used to compare the interlock and noninterlock groups during installation, after installation, and for the entire period up to December 2004. Results indicate a reduction in recidivism of 65% during installation. After removal, there was no significant difference in recidivism rates in a 3-year follow-up period. Following all offenders for 4 years, including both the period while the interlock was installed and the period after its removal, indicates that the difference in recidivism achieved during installation, though not increased, is maintained, so at the end of 4 years, interlock users still have lower total recidivism than nonusers. CONCLUSIONS: The magnitude of interlock effectiveness reported here is similar to those in other published studies with comparable samples.     

Interlocks for first offenders: effective?

OBJECTIVE: Vehicle interlocks have been shown to effectively reduce the recidivism of multiple driving-while-impaired (DWI) offenders; however, the evidence for their effectiveness with first offenders has been mixed. Two Canadian studies found that the installation of an interlock reduced first DWI recidivism, but U.S. studies in West Virginia and California failed to find a significant reduction in recidivism for first DWI offenders in interlock programs. The objective of this study was to determine the extent to which such devices were effective with first offenders in New Mexico. METHODS: This study compared 1,461 first offenders, who installed interlocks in New Mexico between January 1, 2003, and December 1, 2005, with 17,562 first offenders convicted during the same period who did not install the units. Cox multivariate proportional hazards regression (CMVPHR) was used to compare recidivism rates during three periods: while the interlock was on the vehicles of offenders who installed them, after those offenders removed the units until the end of the study period (approximately 2 years), and for the combined period (both while the interlock was installed and after it was removed). RESULTS: While the device was on the vehicles of the interlock group, their recidivism rate, 2.6% per year of exposure, was significantly less than the 7.1% per year rate of the comparison group (CMVPHR hazard ratio = 0.39, p < 0.0001). After the device was removed, the annualized recidivism rate of the interlock group increased to 4.9% per year of exposure, which was less than the 6.7% rate of the comparison group, but the hazard ratio was not statistically significant (CMVPHR hazard ratio = 0.82, p = 0.16). When the combined periods (interlock on and off) were considered, the interlock group had a recidivism rate of 3.9% per year, which again was significantly lower than the 6.8% rate for the comparison group (CMVPHR hazard ratio = 0.61, p < 0.0001). CONCLUSION: The study provides evidence that interlocks are as effective with first offenders (approximately 60% reduction in recidivism when on the vehicle) as they are for multiple offenders. In addition, the benefits of requiring an interlock for first offenders exceed the costs by a factor of three.     

The impact of mandatory versus voluntary participation in the Alberta ignition interlock program

Research has demonstrated that participation in an interlock program significantly reduces the likelihood of subsequent driving while intoxicated (DWI) convictions at least so long as the interlock device is installed in the vehicle. Despite the growing number of jurisdictions that allow interlock programs and the demonstrated success of these programs, the proportion of DWI offenders who actually have the device installed is minimal. In an effort to increase the proportion of offenders using interlocks, some jurisdictions require offenders to install an interlock as a condition of license reinstatement whereas others merely offer offenders a reduction in the period of hard suspension if they voluntarily participate in an interlock program. The objective of the present study was to determine the extent to which voluntary interlock participants are more or less successful in terms of subsequent recidivism than those for whom interlock program participation has been mandated. The issue was addressed using data from the interlock program in Alberta, Canada, which provides for both mandatory and voluntary participation. The recidivism experience of voluntary and mandatory interlock participants was examined both during and after the period of interlock installation. Cox regression revealed that, after controlling for (or equating) the number of prior DWI offenses, the survival rates of DWI offenders who were ordered to participate in the interlock program did not differ from those of voluntary participants. These results suggest that further use of mandatory interlock programs should be just as successful as voluntary programs when offenders share characteristics with those studied in Alberta.     

The impact of mandatory versus voluntary participation in the Alberta ignition interlock program

Research has demonstrated that participation in an interlock program significantly reduces the likelihood of subsequent driving while intoxicated (DWI) convictions at least so long as the interlock device is installed in the vehicle. Despite the growing number of jurisdictions that allow interlock programs and the demonstrated success of these programs, the proportion of DWI offenders who actually have the device installed is minimal. In an effort to increase the proportion of offenders using interlocks, some jurisdictions require offenders to install an interlock as a condition of license reinstatement whereas others merely offer offenders a reduction in the period of hard suspension if they voluntarily participate in an interlock program. The objective of the present study was to determine the extent to which voluntary interlock participants are more or less successful in terms of subsequent recidivism than those for whom interlock program participation has been mandated. The issue was addressed using data from the interlock program in Alberta, Canada, which provides for both mandatory and voluntary participation. The recidivism experience of voluntary and mandatory interlock participants was examined both during and after the period of interlock installation. Cox regression revealed that, after controlling for (or equating) the number of prior DWI offenses, the survival rates of DWI offenders who were ordered to participate in the interlock program did not differ from those of voluntary participants. These results suggest that further use of mandatory interlock programs should be just as successful as voluntary programs when offenders share characteristics with those studied in Alberta.     

An evaluation of the Swedish ignition interlock program

The Swedish alcohol ignition interlock program for driving while intoxicated (DWI) offenders, both first-time as well as multiple offenders, was launched as a pilot project in 1999. It is a volunteer program and differs in some respects from other programs: It covers a period of 2 years, it includes very strict medical regulations entailing regular checkups by a physician, it does not require a prior period of hard suspension, and it focuses strongly on changes in alcohol habits. Records from the 5 years prior to the offence showed that DWI offenders are generally in a high-risk category long before their offense, with a four to five times higher accident rate (road accidents reported by the police) and a three to four times higher rate of hospitalization due to a road accident. Only 12% of the eligible DWI offenders took part in the program and, of these, 60% could be diagnosed as alcohol dependent or alcohol abusers. During the program, alcohol consumption is monitored through self-esteem questionnaires (AUDIT) and five different biological markers. Our data show a noticeable reduction in alcohol consumption among the interlock users. This, combined with the high rate of compliance with the regulations, probably accounts for the fact that there was no case of recidivism during the program. Preliminary findings also suggest a reduction in the annual accident rate for interlock users while in the program. It still is too early to draw any conclusions concerning the rate of recidivism after completion of the program due to an insufficient amount of data for analysis. Nevertheless, the preliminary results are so promising that the program will now be expanded to cover all of Sweden as well as to include all driver's license categories.     

An evaluation of the implementation of ignition interlock in California

Problem: This study evaluates the degree to which courts have implemented California's ignition interlock program, and surveys judges and district/city attorneys to identify barriers to implementing a successful interlock program. Method: There are three parts to the evaluation. In the first, a sample of drivers arrested for driving on a driving under the influence (DUI)-suspended driver license was examined to calculate the rate at which courts order interlocks for DUI-suspended drivers, as required by California law. The second part of the study used Department of Motor Vehicle (DMV) records to count the statewide rate of court-ignition interlock device (IID) orders across time and jurisdictions. The final part surveyed judges, district/city attorneys, and offenders installing an interlock to obtain information about their use of interlock, barriers to implementing an interlock program, and the effectiveness of the devices in preventing drinking and driving. Results: It was found that conviction rates for driving while suspended are low; that judges order interlocks for only a fraction of the convicted driving-while-suspended (DWS) offenders who should receive such an order; and that the majority of offenders who are ordered by the court to install an ignition interlock in their vehicle do not do so. Impact on Industry: Any successful interlock program will need to find a way to balance the inability of many offenders to pay for the devices, with the need for the industry to remain economically viable.     

Attitudes toward mandatory ignition interlocks for all offenders convicted of driving while intoxicated

Introduction: Ignition interlocks are effective in reducing alcohol-impaired driving recidivism for all offenders, including first-time offenders. Despite their effectiveness, interlock use among persons convicted of driving while intoxicated from alcohol (DWI) remains low. This cross-sectional survey of U.S. adults assessed public support for requiring ignition interlocks for all convicted DWI offenders including first-time offenders. The goal was to update results from a similar 2010 survey in light of new state requirements and increased interlock installations. Methods: Questions were included in the Porter Novelli FallStyles survey, which was fielded from September 28 to October 16, 2015. Participants were the 3,536 individuals who provided an opinion toward requiring ignition interlocks for all offenders. For analyses, opinion toward requiring interlocks for all offenders was dichotomized into ‘agree’ and ‘neutral/disagree.’ To handle missing data, 10 imputed datasets were created and pooled using fully conditional specification (FCS). Results: Fifty-nine percent of adults supported requiring interlocks for all DWI offenders. Multivariate analysis revealed that persons who did not report alcohol-impaired driving (AID) were 60% more likely to support requiring interlocks than those who reported AID. Having heard of interlocks also increased support. Support was generally consistent across demographic subgroups. Conclusions: Interlocks for all offenders have majority support nationwide in the current survey, consistent with previous reports. Support is lowest among those who have reported alcohol-impaired driving in the past 30 days. These results suggest that communities with higher levels of alcohol-impaired driving may be more resistant to requiring ignition interlocks for all convicted DWI offenders. Future studies should examine this association further. Practical applications: These results indicate that the majority of adults recognize DWI as a problem and support requiring interlocks for all offenders.     

Transdermal alcohol monitoring combined with contingency management for driving while impaired offenders: A pilot randomized controlled study

Objectives: In a pilot randomized controlled trial of contingency management (CM) and transdermal alcohol monitoring (TAM) with offenders driving while impaired by alcohol (DWI), perceptions regarding the acceptability of a TAM device, recruitment issues, and the impact of CM and TAM on alcohol use over a 6-week period were evaluated. The results aimed to inform the design of future trials and programs involving CM and TAM for DWI remediation.

Methods: TAM devices were affixed to 37 voluntary, community-recruited male DWI offenders with problem alcohol use. They were randomized to one of 3 groups: (1) CM; (2) alcohol use feedback (FB); and (3) TAM device only (CTL). Quantitative and qualitative data were gathered on the acceptability of TAM devices and recruitment, and alcohol use was monitored via TAM and self-report.

Results: The TAM device was perceived positively, with benefits for reducing drinking noted. Nevertheless, some of its inconveniences appeared to influence participant recruitment and attrition, including its large size and limited water resistance. TAM data revealed a significant main effect of time for reduction in weekly peak transdermal alcohol concentration (P = .02), with a decrease between means of weeks 1 and 6 (M = 0.15, SE = 0.02 vs. M = 0.09, SE = 0.02; P = .005). No significant group effect was detected.

Conclusions: TAM is a viable adjunct to CM with DWI offenders, though the TAM device used here may influence both study recruitment and adherence. These findings can guide the design of future studies into CM and TAM for DWI remediation.     

Effects of enhanced sanctions for high-BAC DWI offenders on case dispositions and rates of recidivism

Implemented January 1, 1998, Minnesota's high-BAC law mandates more severe administrative pre-conviction penalties and more severe post-conviction penalties for offenses with BACs > or = 0.20%. Most notably, the law provides for the administrative impoundment of the license plate of first-time DWI offenders with BACs > or = 0.20. During the three years after the law took effect, a large majority of first-time and repeat offenders with BACs > or = 0.20% did, in fact, receive high-BAC administrative dispositions and/or high-BAC court convictions, which carried more severe penalties. For example, in 1998 85.6% of first offenders with BACs > or = 0.20% received a high-BAC administrative disposition and/or a high-BAC court conviction; 65.0% received both high-BAC administrative and high-BAC court dispositions. The proportion of high-BAC first-time offenders who received the statutory high-BAC dispositions declined from 1998 to 1999 and 2000. Based on survival analysis, the one-year recidivism rate among first offenders arrested in 1998 with BACs > or = 0.20% was significantly lower than for offenders with BACs 0.17-0.19% (who also had relatively high BACs but were not subject to enhanced sanctions), after controlling for age and gender. There were similar, but not significant, results for first offenders arrested in 1999.     

Controlling impaired driving through vehicle programs: an overview

The growing recognition of the problem presented by illicit vehicle operation by those whose license has been suspended for driving while intoxicated (DWI) has led to the increasing use of vehicle sanctions. These sanctions include vehicle impoundment and forfeiture, vehicle registration cancellation, and vehicle interlocks as penalties for DWI and driving while suspended (DWS). This article reviews the current information available on the use and effectiveness of vehicle sanctions for reducing offender recidivism. In the United States, 14 states have impoundment laws that are widely used as sanctions for both DWI and DWS, with the length of the impoundment increasing with the number of previous offenses. These laws have been shown to reduce recidivism while the vehicle is in custody and, to a lesser extent, even after the vehicle has been released. Vehicle impoundment is also widely used in Canada and New Zealand. Although a larger number of U.S. states have laws providing for vehicle forfeiture for DWI or DWS, this sanction tends to be limited to multiple offenders and therefore impacts fewer drivers. Cancellation of the vehicle registration and the confiscation of the vehicle plates are increasing in popularity because the vehicle tags are the property of the state, rather than the vehicle owner. Vehicle alcohol interlocks have proven to be an effective method for reducing DWI offender recidivism while they are on the car, but appear to produce only limited post-treatment behavior change. Interlocks are widely used in the United States and Canada and are beginning to be implemented in Europe and Australia. The issues that arise in implementing vehicle sanction programs are discussed and the actions taken by states to deal with them are described.     

Oregon's habitual traffic offender program: An evaluation of the effectiveness of license revocation

This report presents the results of a study of the effectiveness of license revocation for habitual offenders. Drivers whose licenses were revoked were compared with a similar group of drivers whose licenses were not revoked. All revoked drivers had significantly fewer nonmajor violations than did the control drivers. Revoked drivers who received the revocation notice (47%) also had significantly fewer accidents and major violations. Moreover, revoked drivers demonstrated a significant change in the pattern of violation types after revocation. It was concluded that: (a) revocation seems to be an effective way to deter habitual traffic offenders, because habitual offenders whose licenses are revoked have fewer traffic involvements than would be expected if they were not revoked; (b) license revocation would be more effective if the rate of delivery of the revocation notice was higher; and (c) even though many habitual offenders drive illegally after revocation, there is evidence that improved driving behavior, as well as reduced exposure, contributes to the effectiveness of the program.     

The use of proactive risk management to reduce emergency service vehicle crashes among firefighters

IntroductionEmergency service vehicle crashes (ESVCs), including rollovers and collisions with other vehicles and fixed objects, are a leading cause of death among U.S. firefighters. Risk management (RM) is a proactive intervention to identifying and mitigating occupational risks and hazards. The goal of this study was to assess the effect of RM in reducing ESVCs. Methods: Three fire departments (A, B and C), representing urban and suburban geographies, and serving medium to large populations, participated in facilitated RM programs to reduce their ESVCs. Interventions were chosen by each department to address their department-specific circumstances and highest risks. Monthly crash rates per 10,000 calls were calculated for each department an average of 28 months before and 23 months after the start of the RM programs. Interrupted time series analysis was used to assess the effect of the RM programs on monthly crash rates. Poisson regression was used to estimate the number of crashes avoided. Economic data from Department A were analyzed to estimate cost savings. Results: Department A had a 15.4% (P = 0.30) reduction in the overall monthly crash rate immediately post-RM and a 1% (P = 0.18) decline per month thereafter. The estimated two-year average cost savings due to 167 crashes avoided was $253,100 (95%CI= $192,355 – $313,885). Department B had a 9.7% (P = 0.70) increase in the overall monthly crash rate immediately post-RM and showed no significant changes in their monthly crash rate. Department C had a 28.4% (P = 0.001) reduction in overall monthly crash rate immediately post-RM and a 1.2% (P = 0.09) increase per month thereafter, with an estimated 122 crashes avoided. Conclusions: RM programs have the potential to reduce ESVCs in the fire service and their associated costs; results may vary based on the interventions chosen and how they are implemented. Practical applications: Risk management may be an effective and broadly implemented intervention to reduce ESVCs in the US fire service.     

Effects of an absenteeism feedback intervention on employee absence behavior†

The purpose of this study was to test the effects of an Absenteeism Feedback Intervention (AFI) on employee absenteeism. Three hundred and seventy‐one employees working in 14 experimental and 13 control groups in a medium sized hospital participated in the study. Employees working in the experimental groups received absenteeism feedback at three time periods that provided them with information about their own number of absent days and episodes (sequential days counted as a single absence episode) as well as the average of their work and occupational group. Comparisons of absent days and episodes between the AFI and control groups indicate some support for the effectiveness of the intervention. In particular, there was a reduction in absent days and episodes for employees with higher than average absenteeism during the previous year but who were not extreme offenders. The research and practical implications of the AFI for reducing employee absenteeism are discussed. Copyright © 2001 John Wiley & Sons, Ltd.     

Alcohol-impaired motorcyclists versus car drivers: A comparison of crash involvement and legal consequence from adjudication data

Introduction: Driving under the influence (DUI) increases the probability of motor-vehicle collisions, especially for motorcycles with less protections. This study aimed to identify commonalities and differences between criminally DUI offenses (i.e., with a blood alcohol concentration (BAC) of 80 mg/dL or higher) committed by motorcyclists and car drivers. Methods: A total of 10,457 motorcycle DUIs and 8,402 car DUIs were compared using a series of logistic regression models, using data extracted from the documents of adjudication decisions by the courts of Jiangsu, China. Results: The results revealed that offenders from the high-BAC group (i.e., 200 mg/dL or higher) accounted for more than 20% of the total DUI offenses, and were more likely to be involved in a crash and punished with a longer detention. Motorcyclists had a higher likelihood of crash involvement, and were also more likely to be responsible for single-vehicle crashes associated with higher odds of injury sustained, compared to alcohol-impaired car drivers. In the verdict, motorcycle offenders were more likely to receive a less severe penalty. Conclusions: Interventions are clearly required to focus on reducing in the high-BAC group of offenders. For alcohol-impaired motorcyclists, their risks of crash and injury against BAC climb more steeply than the risks for car drivers. The factors including frequent occurrences, uncertainty of detection, and short-term sentences may weaken the deterrence effect of the criminalization of motorcycle DUI. Practical Applications: The traffic-related adjudication data support traffic safety analysis. Strategies such as combating motorcycle violations (e.g., unlicensed operators or driving unsafe vehicles), undertaking education and awareness campaigns, are expected for DUI prevention.     

Marijuana-, alcohol-, and drug-impaired driving among emerging adults: Changes from high school to one-year post-high school

IntroductionDriving while impaired (DWI) increases the risk of a motor vehicle crash by impairing performance. Few studies have examined the prevalence and predictors of marijuana, alcohol, and drug-specific DWI among emerging adults.MethodsThe data from wave 3 (W3, high school seniors, 2012, N = 2407) and wave 4 (W4, one year after high school, N = 2178) of the NEXT Generation Health Study with a nationally representative cohort. W4 DWI (≥ 1 day of past 30 days) was specified for alcohol-specific, marijuana-specific, alcohol/marijuana-combined, illicit drug-related DWI. Multinomial logistic regression models estimated the association of W4 DWI with W3 covariates (perceived peer/parent influence, drinking/binge drinking, marijuana/illicit drug use), and W4 environmental status variables (work/school/residence) adjusting for W3 overall DWI, demographic, and complex survey variables.ResultsOverall DWI prevalence from W3 to W4 changed slightly (14% to 15%). W4 DWI consisted of 4.34% drinking-specific, 5.02% marijuana-specific, 2.41% drinking/marijuana combined, and 3.37% illicit drug-related DWI. W3 DWI was significantly associated with W4 alcohol-related and alcohol/marijuana-combined DWI, but not other DWI. W3 marijuana use, binge drinking, and illicit drug use were positively associated with W4 marijuana-specific, alcohol/marijuana-combined, and illicit drug-related DWI, respectively. W3 friend drunkenness and marijuana use were positively associated with W4 alcohol-specific and marijuana-related DWI, respectively. W3 peer marijuana use was negatively associated with W4 alcohol-specific DWI.ConclusionsDriving under the influence of alcohol, marijuana, and illicit drugs is a persistent, threatening public health concern among emerging U.S. adults. High school seniors' binge drinking as well as regular alcohol drinking and marijuana/illicit drug use were independently associated with respective DWI one year after high school. Peer drunkenness and marijuana use in high school may be related to subsequent DWI of emerging adults.Practical applicationsThe results support the use of injunctive peer norms about getting drunk and smoking marijuana in guiding the development of prevention programs to reduce youth DWI.     

Improved recovery of repeat intoxicated drivers using fingernails and blood spots to monitor alcohol and other substance abuse

Objectives: This study reports the results of a pilot program in Kenosha County that used a combination of direct biomarkers extracted from blood spots and nails to monitor repeat intoxicated drivers for their use of alcohol and drugs with a detection window spanning from 3 weeks to several months. The objectives were to test whether the direct biomarkers phosphatidylethanol (PEth), ethylglucuronide (EtG), and 5 drug metabolites would (1) help assessors obtain a more objective evaluation of repeat offenders during the assessment interview, (2) allow for timely identification of relapses and improve classification of drivers into risk categories, and (3) predict recidivism by identifying offenders most likely to obtain a subsequent operating while intoxicated (OWI) offense within 4 years of enrollment in the program.

Methods: All (N = 261) repeat offenders were tested using PEth obtained from blood spots and EtG obtained from fingernails; 159 participants were also tested for a 5 drugs of abuse nail panel. Drivers were tested immediately after the assessment interview (baseline) and at 3, 6, 9, and 12 months after baseline. Based on biomarker results and self-reports of abstinence, offenders were classified into different risk categories and required to follow specific testing timelines based on the program's decision tree.

Results: The baseline analysis shows that 60% of drivers tested positive for alcohol biomarkers (EtG, PEth, or both) at the assessment interview, with lower detection rates (0–11%) for the 5 drug metabolites. The comparison of biomarkers results to self-reports of abstinence identified 28% of all offenders as high risk and assigned them to more frequent testing and more intense monitoring. The longitudinal analysis shows that 56% (completers) of participants completed the program successfully and the remaining 44% (noncompliant) terminated prematurely. Two thirds (68%) of the completers were able to reduce or control their drinking and one third relapsed at least one time during their mandated monitoring periods. After a brief intervention by the assessors, 79% of relapsers tested negative for biomarkers in their repeat tests. The rearrest analysis showed that offenders classified in the noncompliant and relapsers groups were 7 times more likely to receive a new OWI 4 years after enrollment compared to drivers classified as abstainers or controllers. Refractory drivers were monitored the longest and reported no subsequent rearrests.

Conclusion: These findings demonstrate the benefits of more individualized interventions with repeat OWI offenders and calls for further development of multimodal approaches in traffic medicine including those that use direct alcohol biomarkers as evidence-based practices to reduce recidivism.