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.     

Breath alcohol ignition interlock devices: controlling the recidivist

This study compares the recidivism rates of two groups of Illinois drivers who had their driver's licenses revoked for alcohol-impaired driving and who received restricted driving permits. Drivers in both groups had more than two driving under the influence (DUI) actions against their record within 5 years or were classed as level III alcohol dependents. Drivers in one group were required to install breath alcohol ignition interlock devices in their vehicles and drivers in the other group were not. The research found that drivers with the interlock were one-fifth as likely to be arrested for DUI during the 1 year the device was installed as the comparison group, which did not have the device. However, once the ignition interlock was removed, drivers in this group rapidly returned to DUI arrest rates similar to those in the comparison group. These findings echo previous literature. Additionally, the study showed that this voluntary program in Illinois reached only 16% of the drivers who met the requirements for installing the interlock device. Finally, this study found that individuals who were removed from the interlock program and returned to revoked status continued to drive. Within 3 years, approximately 50% of this latter group were involved in a crash or were arrested for DUI or with an invalid driver's license. Conclusions drawn from the study suggest that the breath alcohol ignition interlock device is effective in preventing continued driving while impaired. However, the large-scale effectiveness of the device is limited since most of the drivers eligible for the device do not have it installed. To have a significant impact, the interlock device must represent a better alternative to drivers whose licenses were suspended or revoked because of alcohol arrests compared to remaining on revoked status without having the device installed. Finally the research suggests that, given the rapid return to predevice recidivism, the devices should remain installed until drivers can demonstrate an extended period of being alcohol free.     

Breath alcohol ignition interlock devices: controlling the recidivist

This study compares the recidivism rates of two groups of Illinois drivers who had their driver's licenses revoked for alcohol-impaired driving and who received restricted driving permits. Drivers in both groups had more than two driving under the influence (DUI) actions against their record within 5 years or were classed as level III alcohol dependents. Drivers in one group were required to install breath alcohol ignition interlock devices in their vehicles and drivers in the other group were not. The research found that drivers with the interlock were one-fifth as likely to be arrested for DUI during the 1 year the device was installed as the comparison group, which did not have the device. However, once the ignition interlock was removed, drivers in this group rapidly returned to DUI arrest rates similar to those in the comparison group. These findings echo previous literature. Additionally, the study showed that this voluntary program in Illinois reached only 16% of the drivers who met the requirements for installing the interlock device. Finally, this study found that individuals who were removed from the interlock program and returned to revoked status continued to drive. Within 3 years, approximately 50% of this latter group were involved in a crash or were arrested for DUI or with an invalid driver's license. Conclusions drawn from the study suggest that the breath alcohol ignition interlock device is effective in preventing continued driving while impaired. However, the large-scale effectiveness of the device is limited since most of the drivers eligible for the device do not have it installed. To have a significant impact, the interlock device must represent a better alternative to drivers whose licenses were suspended or revoked because of alcohol arrests compared to remaining on revoked status without having the device installed. Finally the research suggests that, given the rapid return to predevice recidivism, the devices should remain installed until drivers can demonstrate an extended period of being alcohol free.     

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.     

Preventing highway crashes by raising the legal minimum age for drinking: An empirical confirmation

In recent years there has been increased interest in reducing the massive social costs due to alcohol-related motor vehicle crashes. Raising the legal minimum age for purchase and consumption of alcohol beverages has been proposed as one way to reduce alcohol-related crashes among young drivers. Currently, many states are raising the legal age, in contrast to the trend towards lower legal drinking ages in the early 1970s. Recent studies of the effects of raising the drinking age are reviewed, and results from a controlled multiple time-series evaluation of the experience in Michigan are presented. Significant 11 to 28% reductions in alcohol-related crash involvements are shown to be attributable to the raised drinking age in Michigan. Suggestions for further research and discussion of policy implications are included.     

Driver's alcohol and passenger's death in motor vehicle crashes

OBJECTIVE: Previous studies on alcohol involvement associated with fatal injury in traffic crashes have focused on the drivers, but the passenger's view is not well known. This study (1) analyzes the relationship between passenger's death and alcohol inebriation of the driver and (2) estimates the role of alcohol as the cause of a crash by examining who was at fault, sober, or inebriated. METHOD: The study includes all motor vehicle passengers (n = 420) who died in crashes in Sweden 1993 through 1996 and were medicolegally autopsied. Autopsy reports from the Departments of Forensic Medicine, including toxicological analyses, and police reports were studied. Presence of alcohol among drivers was based on blood and breath tests. RESULTS: One-fifth of the fatally injured passengers and one-fifth of the tested drivers were under the influence of alcohol. The youngest drivers had the highest prevalence of drunken driving. Drivers at fault were alcohol positive in 21% of these crashes and drivers were not at fault in 2% of these crashes. In 53% of the crashes where both the passenger and driver were alcohol positive, the passenger had a lower alcohol concentration than the driver. Children (<16 years) comprised 15% of the killed passengers. Notably, the children were riding with a driver who was under influence of alcohol in 13% of these crashes. Alcohol involvement was not tested in half of the surviving drivers. CONCLUSIONS: The data show that 20% of both passengers and drivers were under the influence of alcohol. Increased testing of surviving drivers regarding alcohol and other drugs is recommended.     

Preventing impaired driving using alcohol policy

Considerable progress has been made in the reduction of impaired driving crashes during the last two decades. Much of this progress is attributable to strengthening laws against impaired driving along with vigorous enforcement efforts aimed at deterring impaired driving. In addition, many useful strategies can also be applied that focus on the control of alcohol availability, use, and promotion. Alcohol policies include controls on the price of alcohol, the location, density, and opening hours of sales outlets, controls on the social availability of alcohol, and on the promotion and advertising of alcohol. Enforcement of these policies is an important aspect of their effectiveness. These strategies have been shown to be effective or promising in reducing impaired driving as well as other consequences related to alcohol use and misuse.     

Surrogate measures of alcohol involvement in fatal crashes: Are conventional indicators adequate?

The problem of alcohol-related highway fatalities has led a majority of states to enact new legislative countermeasures. Because few states consistently collect information on alcohol involvement in fatal crashes, the evaluation of the effectiveness of these countermeasures has relied on surrogate measures of alcohol involvement. Using data from the U.S. Department of Transportation's Fatal Accident Reporting System (FARS), this study addresses the following questions: (a) Which of the several surrogate measures used are most likely to reflect alcohol involvement in fatal crashes? and (b) Do the trends in these surrogate measures provide an accurate appraisal of the true trends in alcohol-involved fatal crashes? The authors conclude that nighttime fatal crashes are the best surrogate measure of alcohol-involved crashes, but that surrogate measures may not accurately mirror trends in alcohol-involved fatal crashes over time, particularly in small states or over short durations. All drivers in fatal crashes should be given blood alcohol level (BAL) tests to most accurately assess the effects of drunk driving countermeasures.     

Preventing highway crashes by raising the legal minimum age for drinking: The Michigan experience 6 years later

Results of a 6-year follow-up of previous research evaluating the effects of Michigan's December 1978 increase in the legal drinking age from 18 to 21 are reported. Earlier research demonstrated the immediate effect of Michigan's raised legal age in reducing motor vehicle crash involvement among young drivers. The current study examined 6 years of post-law traffic crash data, using Box-Jenkins intervention analysis methods to assess the long-term effects of the raised drinking age. Results revealed long-term ef- fects of the law similar to the initial effects identified earlier. Over the 6-year follow-up period, the rate of involvement in injury-producing single-vehicle nighttime crashes among drivers age 18–20 was 16 % lower than the level ex- pected, had the drinking age law not changed. Police-reported drinking driver crash involvement was down 19%. In contrast to many alcohol-im- paired driving countermeasures, the raised legal drinking age appears to have a long-term effect in reducing motor vehicle crash involvement among young drivers.     

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.     

The effects of drug and alcohol consumption on driver injury severities in single-vehicle crashes

Objective: It is well known that alcohol and drugs influence driving behavior by affecting the central nervous system, awareness, vision, and perception/reaction times, but the resulting effect on driver injuries in car crashes is not fully understood. The purpose of this study was to identify factors affecting the injury severities of unimpaired, alcohol-impaired, and drug-impaired drivers.

Method: The current article applies a random parameters logit model to study the differences in injury severities among unimpaired, alcohol-impaired, and drug-impaired drivers. Using data from single-vehicle crashes in Cook County, Illinois, over a 9-year period from January 1, 2004, to December 31, 2012, separate models for unimpaired, alcohol-impaired, and drug-impaired drivers were estimated. A wide range of variables potentially affecting driver injury severity was considered, including roadway and environmental conditions, driver attributes, time and location of the crash, and crash-specific factors.

Results: The estimation results show significant differences in the determinants of driver injury severities across groups of unimpaired, alcohol-impaired, and drug-impaired drivers. The findings also show that unimpaired drivers are understandably more responsive to variations in lighting, adverse weather, and road conditions, but these drivers also tend to have much more heterogeneity in their behavioral responses to these conditions, relative to impaired drivers. In addition, age and gender were found to be important determinants of injury severity, but the effects varied significantly across all drivers, particularly among alcohol-impaired drivers.

Conclusions: The model estimation results show that statistically significant differences exist in driver injury severities among the unimpaired, alcohol-impaired, and drug-impaired driver groups considered. Specifically, we find that unimpaired drivers tend to have more heterogeneity in their injury outcomes in the presence potentially adverse weather and road surface conditions. This makes sense because one would expect unimpaired drivers to apply their full knowledge/judgment range to deal with these conditions, and the variability of this range across the driver population (with different driving experiences, etc.) should be great. In contrast, we find, for the most part, that alcohol-impaired and drug-impaired drivers have far less heterogeneity in the factors that affect injury severity, suggesting an equalizing effect resulting from the decision-impairing substance.     

Spatial relationships between alcohol outlet densities and drunk driving crashes: An empirical study of Tianjin in China

Introduction: Numerous studies have demonstrated the close relationship between alcohol availability and alcohol-related crashes. However, there is still a lack of spatial empirical analysis regarding this relationship, particularly in large cities of developing countries. Differences in alcohol outlets and drinking patterns in these cities may lead to quite different patterns of crash outcomes. Method: 3356 alcohol-related crashes were collected from the blood-alcohol test report of a forensic institution in Tianjin, China. Density of alcohol outlets such as retail locations, entertainment venues, restaurants, hotels, and companies were extracted based on 2114 Traffic Analysis Zones (TAZ) together with the residential and demographic characteristics. After applying the exploratory spatial data analysis, this research developed and compared the traditional Ordinary Least Square model (OLS), Spatial Lag Model (SLM), Spatial Error Model (SEM) and Spatial Durbin Model (SDM) to explore spatial effects of all the variables. Results: The results of incremental spatial autocorrelation show that the most significant distance threshold of alcohol-related roadway traffic crashes is 3 km. The SDM is found to be the optimal spatial model to characterize the relationship between alcohol outlets and crashes. The number of alcohol-involved traffic crashes is positively related to population density and retail density, but negatively related to the company density, hotel density, and residential density within the same TAZ. Meanwhile, dense population and hotels have reverse spillover effects in adjacent zones. Conclusions: The significant spatial direct effect and spillover effect of alcohol outlet densities on drunk driving crashes should not be neglected. These findings could help improve transportation planning, traffic law enforcement and traffic management for large cities in developing countries.     

酒精蒸气/烟草粉尘两相混合体系最小点火能试验研究

在烟草加工的加香工序,挥发的酒精和搅拌混料产生的烟草粉尘形成气粉混合体系,其燃爆特性相较于单相烟草粉尘有较大变化。对20 L爆炸球进行了部分改造,可完成20℃～80℃环境温度、100%LEL以下酒精蒸气浓度、最大2 J电火花能量组合的气粉混合物的最小点火能测试。选用烘丝和加香烟草粉尘做对比,探究了环境温度和酒精蒸气浓度对酒精蒸气/烟草粉尘两相混合体系点火能的影响规律。结果表明：相同环境温度下,加香烟草粉尘的最小点火能比烘丝烟草粉尘低;加香粉尘、烘丝粉尘及混合体系的最小点火能随环境温度变化的趋势一致,均随温度的升高而降低;加入10%LEL的酒精蒸气后,相同温度下气粉混合体系的最小点火能低于单相烟草粉尘。随着环境温度的升高,二者的差值逐渐减小,酒精蒸气诱导烟草粉尘最小点火能降低的能力逐步减小甚至消失;在电点火条件下,当酒精蒸气浓度低于50%LEL时,气粉混合体系较难被点燃,当酒精蒸气浓度高于75%LEL时,混合体系较易被点燃。     

Validity of police-reported alcohol involvement in fatal motor carrier crashes in the United States between 1982 and 2005

Objective

To examine the validity of police-reported alcohol data for drivers involved in fatal motor carrier crashes.

Material and Methods

We determined the availability of blood alcohol concentration (BAC) and police-reported alcohol data on 157,702 drivers involved in fatal motor carrier crashes between 1982 - 2005 using Fatality Analysis and Reporting System (FARS) data. Drivers were categorized as motor carrier drivers if they operated a vehicle with a gross vehicle weight rating of greater than 26,000 pounds. Otherwise, they were classified as non motor carrier drivers. The sensitivity and specificity of police-reported alcohol involvement were estimated for both driver types.

Results

Of the 157,702 drivers, 18% had no alcohol information, 15% had BAC results, 42% had police-reported alcohol data, and 25% had both. Alcohol information varied significantly by driver, crash, and vehicle characteristics. For example, motor carrier drivers were significantly more likely (51%) to have BAC testing results compared to non motor carrier drivers (31%) (p < 0.001). The sensitivity of police-reported alcohol involvement for a BAC level ≥ 0.08 was 83% (95% CI 79%, 86%) for motor carrier drivers and 90% (95% CI 89%, 90%) for non motor carrier drivers. The specificity rates were 96% (95% CI 95%, 96%) and 91% (95% CI 90%, 91%), respectively.

Conclusions

The sensitivity and specificity of police-reported alcohol involvement are reasonably high for drivers involved in fatal motor carrier crashes. Further research is needed to determine the extent to which the accuracy of police-reported alcohol involvement may be overestimated because of verification bias.

Impact on the Industry

Based on the results of this study, the federal government should continue to work with states to strengthen their strategies to increase chemical testing of all drivers involved in fatal crashes.