Drug Drivers Research Articles

How do perceptions of procedural justice, police legitimacy, and legitimacy of laws influence intentions to drug drive?

Introduction: There is a need for improved drug driving enforcement to promote greater driver compliance with drug driving laws. In Australia, Roadside Drug Testing (RDT) suffers from operational challenges that undermine its effectiveness in reducing drug driving. Objective: To identify potential improvements to RDT, this study investigated the extent to which drivers perceive RDT to be procedurally just and that the policing of drug driving and the associated laws are legitimate. These perceptions were then compared with those applying to Random Breath Testing (RBT) and examined in relation to their respective influence on intentions to drug and drink drive in the future. Method: A sample of 1,483 licensed drivers from three Australian states completed an online survey. Results: Those participants who reported engaging in drug driving perceived RDT to be less procedurally just than non-drug drivers. Similarly, drug drivers perceived the police and associated drug driving laws to be less legitimate than non-drug drivers. Furthermore, drug drivers who had been tested at an RDT operation in the past perceived RDT to be less procedurally just and considered drug driving policing and laws to be less legitimate, compared with the corresponding perceptions of drink drivers who had been tested at an RBT operation. A regression analysis indicated that stronger intentions to drug drive in the future were associated with lower perceptions of police legitimacy and the legitimacy of drug driving laws, but not with the elements of procedural justice. However, follow-up analyses indicated that the influence of procedural justice on intentions was mediated by the two legitimacy variables, thus weakening its direct impact on intentions. Practical applications: The results highlight the need for road safety authorities to enhance the perceived legitimacy of drug driving enforcement and associated laws. Changes to current police practices and/or drug-driving laws may also be needed to enhance the effectiveness of RDT.

Drug driving in Italy. The results of the first roadside drug testing service utilizing on-site confirmatory analysis between 2019 and 2022

BackgroundDrug driving represents a public safety concern, and the size of this issue in Italy is not fully known. Drug testing is composed of two steps: 1) screening and 2) confirmatory analysis. The second step, and the associate medical examination to assess the state of impairment, usually are not performed right after the screening as they require specialized personnel and instrumental equipment that are not historically available at roadblocks. These pitfalls make this process both complicated and time-consuming. MethodsA mobile laboratory was set up in 2019 by the Forensic Lab Service S.r.l. (limited liability company) to improve roadblock timing, planning, as well as to shed light on the extent of the drug driving issue in Italy. Drug screenings were performed using DrugWipe® Saliva testing. Confirmatory analysis was performed on oral fluids by liquid chromatography coupled with tandem mass spectrometry. A dedicated room of the mobile laboratory was also designed for drug driving medical assessment. Result2082 samples were collected during 88 road safety services held in different locations across Italy. In total, 9 % of the tested subjects were positive to both the screening and the confirmatory analysis. The most prevalent illicit drugs found in this study were THC (72 %), followed by cocaine (41 %). Drug drivers were mostly male (93 %) and younger than 30 years of age (58 %). ConclusionsThe prevalence of drivers testing positive for illicit drugs resulted to be higher compared to the results obtained in the DRUID project and to other surveys previously performed in Italy. These data demonstrate the need for control services to improve road safety in regards to drug driving.

What contributes to drug driving? An exploratory investigation into the influence of problematic substance use, roadside testing and alternative transport options

Despite a strong reliance on enforcement approaches to prevent drug driving in Australia, this behaviour is still prevalent. The objective of this study was to investigate the influence of problematic drug use (i.e., showing indications of addiction), exposure to roadside drug testing, the use of detection avoidance strategies, and perceptions relating to alternative transport options on drug driving among illicit drug users. A total of 1,541 licensed drivers from the states of Queensland, New South Wales, and Victoria completed an online survey. The survey collected demographic and problematic substance use information, as well as items assessing drug driving behaviour. Cannabis was reported to be the most commonly used drug (36.0%); the most common drug of problematic use (27.9%), and the drug most often taken prior to driving (43.5%). Observing police operating Roadside Drug Tests (RDT) was more common among the participants than being tested by RDT (35.7% vs 23%). The results indicated a significant association between being a drug driver and observing or being tested by RDT. The drug drivers were significantly more likely to report using a range of strategies to avoid police detection than the non-drug drivers. Similarly, the drug drivers reported that it was more difficult for them to use various alternative transport options than the non-drug drivers. Decision tree analyses found that significant predictors of self-reported drug driving were problematic drug use, holding a provisional or probationary licence, earning a low- or middle-income, and using detection avoidance strategies like remaining watchful for police vehicles and taking back streets. The findings of this study suggest that ongoing improvements to drug driving enforcement will need to be complemented by health-based approaches designed to reduce drug abuse and dependence, and improvements to public transport, in order to achieve a sustainable reduction in drug driving.

Characteristics of crash-involved drink and drug car drivers and motorcyclists

Objective Drug driving is an issue of growing concern among Australian jurisdictions, including South Australia. In order to have an appropriate response to drug driving in regard to policy and enforcement, it is important to have sound knowledge about the patterns of drug use among motorists and the associated risks of this behavior. Method To this end, this study examined the characteristics of 1,277 hospitalized road users in South Australia in the years 2014 to 2017, with reference to whether or not they tested positive for alcohol or other drugs (the three drugs tested for according to the South Australian Road Traffic Act (1961): THC, methamphetamine, MDMA). This examination used a database combining hospital data, police-reported crash data, licensing information, and the result of alcohol and drug tests conducted by Forensic Science SA. Results It was found that more motorists were positive for one or more of the three illicit drugs than for alcohol, reversing long established trends. Comparisons were made between alcohol and drug free motorists, alcohol positive motorists, drug positive motorists, and motorists positive for both drugs and alcohol, with drivers of cars and motorcyclists analyzed separately where possible. Findings include: that those combining drugs and alcohol only comprise a small proportion of hospitalized motorists; that drug drivers tend to be younger than other hospitalized motorists; that drivers are more likely to test positive to alcohol or methamphetamine, while motorcyclists are more likely to test positive to THC; motorists testing positive to drugs and/or alcohol tend to exhibit a range of other risky behaviors; and motorists testing positive to drugs and/or alcohol tend to sustain more severe injuries in the event of a crash. Conclusions Preventing drink and drug driving is important not only for reducing crash numbers but also injury severity in the event of a crash. Substance use differs by road user type and age, which has potential implications for enforcement practices.

The prevalence of drug driving and being caught for a drug driving offense among community-recruited people who use methamphetamine in metropolitan and rural Victoria, Australia

Objective To examine the prevalence, frequency and characteristics of drug driving and being caught for a drug driving offense and their key correlates among people who used methamphetamine in rural and metropolitan areas of Victoria, Australia. Methods Cross-sectional analysis of a sample of 744 people who used methamphetamine. Outcomes included self-reported drug driving (driving within three hours of consuming drugs, yes/no) and having been caught for a drug driving offense (yes/no). Sociodemographic (including rurality) and drug use variables were included in multivariable analyses. Results Of the 511 participants who reported driving in the six months prior to the survey, 407 (80%) reported drug driving (driving within three hours of taking an illicit drug). Most drug drivers (92.6%) reported taking methamphetamine (in combination with other drugs (59.5%) or in isolation (33.2%)) before driving. Most reported drug driving daily (31%) or weekly (25%), with passengers often (31%) or sometimes (28%). Most reported believing their driving was not at all impaired (49%), or only slightly impaired (32%) when preceded by drug taking. Multivariable analysis revealed that drug driving was not associated with rurality, nor with other socio-demographic characteristics. However, participants residing outside metropolitan areas were more likely to report having been caught previously for a drug driving offense (Adjusted odds ratio [aOR] = 1.93, 95% CI = 1.18–3.16). Conclusions The majority of people within this cohort of people who used methamphetamine reported drug driving. An enhanced focus on public health campaigns and strategies to prevent drug driving is needed.

Deaths associated with MDMA in the period 2000-2019.

The use of MDMA (3,4-methylenedioxymethamphetamine), also known as ecstasy, has increased in Norway in recent years. Since MDMA has the potential to be toxic and cause death, we studied whether increased availability and use correlates with the increase in MDMA-associated deaths. The study includes post-mortems with findings of MDMA in blood, linked to information about cause of death from the Norwegian Cause of Death Registry. These data were compared with the number of arrested drug drivers with MDMA detected in their blood as well as annual seizure statistics from Kripos (The National Criminal Investigation Service) in the period 2000-2019. In the period 2000-2019, MDMA was detected in 142 fatalities, and the cause of death was known for 132 of these. The number of annual MDMA-associated deaths varied from 1 to 18. The median MDMA concentration among the fatalities increased from 1.9 µmol/L (interquartile range (IQR) 0.9 to 5.0) in 2000-2004 to 3.8 µmol/L (1.4 to 12.0) in 2015-2019. In 47/132 (36%) of cases, MDMA and other central nervous system (CNS) stimulant drugs contributed to the death. Among arrested drug drivers with detected MDMA, the annual number of detected cases was 7-262 in this period, but the median concentration remained stable. MDMA may have contributed to numerous deaths in Norway. Increased availability, increased use and increased strength of contents seem to be significant.

A systematic review of factors associated with illegal drug driving

Drug driving is a serious problem worldwide that can increase the risk of road crashes. This systematic review seeks to identify factors associated with drug driving (i.e., driving after consuming drugs other than alcohol) to highlight gaps in existing knowledge and inform the design of more effective countermeasures. A search of the literature was conducted for the period January 1, 2005 to July 31, 2021 using six different databases. The search protocol followed PRISMA guidelines and was registered in PROSPERO (#CRD42021234616). Studies that met inclusion criteria compared drug drivers with either non-drug drivers, alcohol-only drivers or drug drivers from an earlier time period, to identify factors specifically associated with drug driving, rather than common to all drivers. Two hundred and nineteen publications met the inclusion criteria and were included within the review. Based on the findings, a logic model was developed that presents the factors associated with drug driving. Various sociodemographic, psychosocial and legal factors emerged as the main factors associated with illegal drug driving. At the sociodemographic and psychological levels, drug drivers were more likely to be single, young males who often drive after using cannabis and who score high on sensation-seeking and impulsivity scales. The key social factor found to be associated with drug driving was peer acceptance/disapproval of the behaviour. At the legal level, the review suggested that the effectiveness of current enforcement approaches to drug driving vary among jurisdictions around the world due to differences in the level of perceived certainty of apprehension and the chances of punishment avoidance. Future research into the anticipated and actual rewards for drug driving is needed to inform the development of more effective countermeasures.

Hit and miss: a comparison of targeted and randomised roadside drug testing (RDT)

PurposeThis study first aimed to investigate the differences in drug driver detection rates between a trial of randomised and targeted enforcement operations. The second aim was to identify which indicator categories are most commonly used by police to target drug drivers and to assess the effectiveness of targeted drug testing. Finally, this study aimed to quantify what specific indicators and cues (of the overarching categories) triggered their decision to drug test drivers and which indicators were most successful.Design/methodology/approachThis research examined the detection rates in a trial comparison of randomised and targeted roadside drug testing (RDT) operations as well as the methods utilised by police in the targeted operations to identify potential drug driving offenders.FindingsVisual appearance was by far the most commonly utilised indicator followed by age, police intelligence on prior charges, vehicle appearance and behavioural cues. However, the use of police intelligence was identified as the most successful indicator that correlated with positive oral fluid testing results. During the randomised RDT operations, 3.4% of all drivers who were tested yielded a positive roadside oral fluid result compared to 25.5% during targeted RDT operations.Research limitations/implicationsThe targeted RDT approach, while determined to be an effective detection methodology, limits the overall deterrent effect of roadside testing in a more general driving population, and the need for a balanced approach to ensure detection and deterrence is required. This study highlights that by focussing on night times for randomised RDT operations and the identified effective indicators for targeted operations, an effective balance of deterrence and detection could be achieved.Practical implicationsWhile the presence of a single indicator is not indicative of a drug driver, this study highlights for police which indicators currently used are more effective at detecting a drug driver. As a result, police could adapt current RDT procedures to focus on the presence of these indicators to support drug driver detection.Originality/valueThis is a world-first study that examines both randomised and targeted roadside drug testing. This study controls for location and time of day while using the same police unit for roadside testing, thus is able to make direct comparisons between the two methodologies to determine the effectiveness of police targeting for roadside drug testing. Furthermore, this study highlights which indicators used by police results in the highest rate of positive roadside drug tests.

The relationship between traffic and non-traffic offending in Western Australia

Self-selection policing is an approach whereby serious underlying criminality is detected by an offender’s minor crimes (known as trigger offences). Strategic offences are offences that indicate an increased likelihood that the associated offender will engage in later offending. The purpose of this study was to determine if first-time serious traffic offending in Western Australia indicates previous and/or future non-traffic criminality, thereby demonstrating the utility of serious traffic offences as trigger offences and strategic offences. The authors collated the crime data of all first-time serious traffic offenders in Western Australia between December 2004 and December 2014. Using this data, survival analyses were conducted to determine if and when a first-time serious traffic offender committed an initial non-traffic offence within 10 years of their first serious traffic offence. When comparing this data to data from the Australian Bureau of Statistics, the authors found that first-time serious traffic offenders are more likely than the average Western Australian to have a previous or future initial non-traffic offence. Some groups of first-time traffic offenders were more likely to commit non-traffic offences than others including males, individuals under the age of 25, drug drivers and drivers without authority. These results support the use of first-time serious traffic offences as trigger/strategic offences and could be used to identify and divert traffic offenders with versatile criminal histories and traffic offenders at risk of future criminal activity.

Differences in the risk profiles of drunk and drug drivers: Evidence from a mandatory roadside survey

BackgroundThe study assesses the prevalence rates of alcohol- and drug-involved driving in Catalonia (Spain). MethodDrivers were randomly selected for roadside testing using a stratified random sampling procedure representative of all vehicles circulating on non-urban roads. Mandatory alcohol and drug tests were performed during autumn 2017. A sample of 6860 drivers were tested for alcohol use, of these 671 were also tested for drugs. Standard procedures were employed by traffic officers to detect alcohol and drug use. Alcohol breath tests were performed with breathalyser devices and on-site drug screening systems were used to test for drugs. ResultsThe prevalence of alcohol use above the legal limit and drug use were 1.2 % (95 % CI: 0.9–1.5 %) and 8.3 % (95 % CI: 5.8–11.2 %), respectively. The most frequent drugs detected were THC (5.6 %, 95 % CI: 3.7–8.0 %), cocaine (3.5 %, 95 % CI: 2.0–5.5 %) and amphetamines (1.6 %, 95 % CI: 0.6–3.4 %). Alcohol use was detected more frequently on conventional roads, at weekends and during night-time hours. Drug use was detected more frequently in young males during daytime hours. ConclusionsDriver risk profiles associated with alcohol use and drug use differ. Positive alcohol use is not a predictor of drug use when controlling for all other factors.

Speeding and impaired driving in fatal crashes—Results from in-depth investigations

Objective The aim of the study was to identify typical patterns of risk factors among speeding and impaired drivers involved in fatal crashes and to suggest countermeasures. Method Results from in-depth investigations of 1,501 fatal passenger car crashes that occurred in Norway from 2005 to 2015 and involved 1,949 passenger cars are summarized. Relationships between speeding (excessive speed, EXC, or inappropriate speed, INAP); driving under the influence (DUI) of alcohol (ALC), drugs (DRUG), or both (MIX); and other driver-, crash-, vehicle-, and road-related variables were investigated. Results Speeding and DUI drivers have in common that they are more often male, unbelted, unlicensed, driving old cars, and involved in single-vehicle crashes under low-volume conditions (nighttime, weekend, low-volume roads). They are also less often fatigued, ill, or suicidal. EXC and ALC drivers are on average younger and they generally show more high-risk behavior than INAP, DRUG, and MIX drivers. In crashes with pedestrians/cyclists and crashes on slippery roads or in winter, INAP drivers are overrepresented and EXC and DUI drivers are underrepresented. Among DRUG and MIX drivers there may be differences according to the type of substance. Conclusions Those drivers who show most types of high-risk behaviors, especially EXC and ALC drivers, are less likely to respond to measures relying on voluntary behavior changes, such as recommended speed, speed warnings, or classical enforcement, although such measures may be effective for INAP and some DRUG drivers. To change the behavior of EXC and ALC drivers, more restrictive measures are called for, such as non-overridable intelligent speed adaptation, vehicle impoundment, or Alcolock.

Police custody following driving under the influence of cannabis: A prospective study

Traffic offences are a common cause of detention in police custody. We hypothesized that drug intoxication while driving could correspond to specific medical conditions of the detainees. Our objective was to evaluate medical features and addictive behaviours of suspected drug drivers and to collect data regarding assaults or injuries in these individuals. We conducted a prospective study (April 2010–December 2011) of suspected drug driving arrestees, who were compared to drink drivers or persons aged over 18 detained for other reasons. Data collected concerned persons’ characteristics, reported assaults, and observed injuries. A total of 205 drivers were tested positive for drugs in blood, 116 were either positive for drugs in urine or saliva and negative in blood, or negative in urine. Cannabis-only users accounted for 201 of 205 drug drivers (98%). Suspected drug driving arrestees had good overall health rating. Drug drivers were younger than controls and requested more rarely medical examination (12% vs. 44%, P<0.0001). They were rarely involved in addiction treatment (3%) and reported assaults or presented traumatic injuries less often than drink drivers and controls (8% vs. 38% and 25%, P<0.0001). Drug drivers were less often alcohol abusers than controls. Their opinion on custody was better than that of controls and they were considered unconditionally fit for detention more frequently (99% vs. 77%, P<0.0001). We conclude that arrested drug drivers were young, healthy, and infrequently reported assaults or presented traumatic injuries, which does not put them in a high risk medical condition. Medical care could include brief interventions on addictive behaviours.

Detection of drugs of abuse in simultaneously collected oral fluid, urine and blood from Norwegian drug drivers

Blood and urine samples are collected when the Norwegian police apprehend a person suspected of driving under the influence of drugs other than alcohol. Impairment is judged from the findings in blood. In our routine samples, urine is analysed if morphine is detected in blood to differentiate between ingestion of heroin, morphine or codeine and also in cases where the amount of blood is too low to perform both screening and quantification analysis. In several cases, the collection of urine might be time consuming and challenging. The aim of this study was to investigate if drugs detected in blood were found in oral fluid and if interpretation of opiate findings in oral fluid is as conclusive as in urine. Blood, urine and oral fluid samples were collected from 100 drivers suspected of drugged driving. Oral fluid and blood were screened using LC-MS/MS methods and urine by immunological methods. Positive findings in blood and urine were confirmed with chromatographic methods. The analytical method for oral fluid included 25 of the most commonly abused drugs in Norway and some metabolites. The analysis showed a good correlation between the findings in urine and oral fluid for amphetamines, cocaine/benzoylecgonine, methadone, opiates, zopiclone and benzodiazepines including the 7-amino-benzodiazepines. Cocaine and the heroin marker 6-monoacetylmorphine (6-MAM) were more frequently detected in oral fluid than in urine. Drug concentrations above the cut-off values were found in both samples of oral fluid and urine in 15 of 22 cases positive for morphine, in 18 of 20 cases positive for codeine and in 19 of 26 cases positive for 6-MAM. The use of cannabis was confirmed by detecting THC in oral fluid and THC-COOH in urine. In 34 of 46 cases the use of cannabis was confirmed both in oral fluid and urine. The use of cannabis was confirmed by a positive finding in only urine in 11 cases and in only oral fluid in one case. All the drug groups detected in blood were also found in oral fluid. Since all relevant drugs detected in blood were possible to find in oral fluid and the interpretation of the opiate findings in oral fluid was more conclusive than in urine, oral fluid might replace urine in driving under the influence cases. The fast and easy sampling is time saving and less intrusive for the drivers.

Cooperation Between Police and Social Treatment Services Offering Treatment to Drink and Drug Drivers—Experience in Sweden

Objective: To describe and analyze a measure that has been introduced in Sweden with the objective of quickly offering treatment for the alcohol or drug problems suspected drink or drug drivers may have. The goal of the measure is that every suspected drink or drug driver shall, as soon as apprehended by the police, be offered contact with the social services or the dependency care and treatment service, which can offer a consultation and, if needed, suitable treatment. Method: Interviews and questionnaire surveys, as well as forms that describe the treatment received by each individual case. Results: About 20 percent of all those who receive the offer from the police accept contact with the social services or the care and treatment service, and approximately 40 percent of these also attend the consultation. There is a favorable fundamental attitude to the method among the participating authorities. However, some shortcomings in application are revealed. One example concerns drug drivers who are offered contact with the social services or the care and treatment service to a considerably lesser extent than drink drivers. Another neglected group are the people who are at first suspected of drink driving but are later found to have an alcohol concentration below the legal limit. Compared with those who have an alcohol concentration above the legal limit, this group is offered contact to a lesser extent and also have a lower propensity to accept the offer. Conclusions: The results indicate a strong support for the method from involved authorities, but participation could be improved by giving more attention to neglected groups.

Tagging of Model Amphetamines with Sodium 1,2‐Naphthoquinone‐4‐sulfonate: Application to the Indirect Electrochemical Detection of Amphetamines in Oral (Saliva) Fluid

AbstractProof‐of‐concept is shown for the indirect electrochemical detection of model amphetamines, D‐amphetamine sulfate and pseudoephedrine, based on the labeling of the amphetamine models with sodium 1,2‐naphthoquinone‐4‐sulfonate (NQS). The presence of the amphetamine models is monitored via either the reduction in the magnitude of the voltammetric peak corresponding to the electrochemical reduction of the quinone functionality of the sodium 1,2‐naphthoquinone‐4‐sulfonate or via growth of a new voltammetric peak related to reaction between the amphetamine model and NQS, both of which are well resolved from one another. The protocol is shown to be successful in artificial saliva and authentic human oral (saliva) fluid. Such a protocol may be particularly attractive for roadside testing of amphetamines in drug drivers.

Preventing cannabis users from driving under the influence of cannabis

Face-to-face, structured interviews were conducted with 320 recent cannabis users in New South Wales, Australia to assess the likely deterrent effects of (a) increasing the certainty of apprehension for driving under the influence of cannabis (DUIC) and (b) doubling the severity of penalties for DUIC. Participants were presented with a drug-driving scenario and asked to indicate their likelihood of driving given that scenario. The perceived risk of apprehension and severity of punishment were manipulated in each scenario to create four different certainty/severity conditions and participants were randomly allocated to one of these four groups. A subsidiary aim was to assess the likely impact of providing factual information about the accident risk associated with DUIC. Recent drug drivers who felt at low risk of accident when DUIC were asked to rate their willingness to drive if convinced that it was dangerous. The results suggested that increasing the certainty but not severity of punishment would produce reductions in cannabis-intoxicated driving among recent cannabis users. Providing factual information about the risks associated with DUIC would appear to have little impact on drug-driving rates among this population.

Indirect detection of substituted phenols and cannabis based on the electrochemical adaptation of the Gibbs reaction

The voltammetric behaviour of 2,6-dichloro-p-aminophenol (PAP) in aqueous solution at an edge plane pyrolytic graphite electrode was explored and its sensitivity to additions of substituted phenols examined. Proof of concept is shown for the electrochemical adaptation of the Gibbs reaction, where reaction of the oxidised form of PAP with substituted phenols provides an indirect methodology for the analytical detection of these compounds. This indirect protocol provides an attractive alterative to the direct electrochemical oxidation of phenolic compounds, since the latter is plagued by electrode passivation, leading to low sensitivity. It is observed that phenol, 4-phenoxyphenol, methylphenol (para and meta), nitrophenol and most importantly, tetrahydrocannabinol, can be detected voltammetrically. Such a protocol is particularly attractive for roadside testing for cannabis in drug drivers.

A review of drug use and driving: epidemiology, impairment, risk factors and risk perceptions.

The existing literature on the prevalence of drug driving, the effects of drugs on driving performance, risk factors and risk perceptions associated with drug driving was reviewed. The 12-month prevalence of drug driving among the general population is approximately 4%. Drugs are detected commonly among those involved in motor vehicle accidents, with studies reporting up to 25% of accident-involved drivers positive for drugs. Cannabis is generally the most common drug detected in accident-involved drivers, followed by benzodiazepines, cocaine, amphetamines and opioids. Polydrug use is common among accident-involved drivers. Studies of impairment indicate an undeniable association between alcohol and driving impairment. There is also evidence that cannabis and benzodiazepines increase accident risk. The most equivocal evidence surrounds opioids and stimulants. It is apparent that drugs in combination with alcohol, and multiple drugs, present an even greater risk. Demographically, young males are over-represented among drug drivers. Although there is an association between alcohol use problems and drink driving, it is unclear whether such an association exists between drug use problems and drug driving. Evidence surrounding psychosocial factors and driving behaviour is also equivocal at this stage. While most drivers perceive drug driving to be dangerous and unacceptable, there is less concern about impaired driving among drug drivers and drink drivers than from those who have not engaged in impaired driving. Risk perceptions differ according to drug type, with certain drugs (e.g. cannabis) seen as producing less impairment than others (e.g. alcohol). It is concluded that drug driving is a significant problem, both in terms of a general public health issue and as a specific concern for drug users.

Drug driving among injecting drug users in Sydney, Australia: prevalence, risk factors and risk perceptions.

To examine the prevalence of drug driving, the prevalence of drug-related motor vehicle accidents, risk perceptions of drug driving and factors associated with drug driving among injecting drug users (IDU). Cross-sectional survey. Sydney, Australia. Three hundred current IDU. Ninety-five per cent had driven a vehicle, 74% in the previous 12 months ('current drivers'). Eighty-seven per cent of life-time drivers reported having drug driven, and 88% of current drivers had drug driven in the previous 12 months. There were no significant sex differences in life-time or recent drug driving. The most common drugs used before driving in the preceding year were: cannabis, heroin, amphetamines and cocaine. A third of life-time drivers reported having had a drug driving accident, with males more likely to have done so, and 9% of current drivers reported a drug driving accident in the previous year. The most common drugs that had been used before the most recent drug driving accident were heroin, cannabis and alcohol. Alcohol was perceived to be the most dangerous substance for driving performance and cannabis the least dangerous. Recent drug drivers perceived drug driving to be less dangerous than non-drug drivers. Recent drug drivers had driven more frequently over the preceding 12 months, had significantly higher levels of dependence, higher frequency of drug use, more extensive polydrug use and were more likely to have used and/or injected a drug in a car in the previous 12 months. Drug driving and drug-related accidents are large-scale public health problems among IDU. These behaviours pose serious risks to IDU themselves and to the broader community.

Illicit drugs and driving: a review of epidemiological, behavioural and psychological correlates

Large numbers of individuals use illicit drugs (e.g. cannabis, heroin, cocaine). The number of people driving vehicles has also increased. There is an increasing overlap between populations of illicit drug users and drivers. This paper describes the magnitude and nature of an illicit drugs and driving problem. The relationship between the consumption of illicit substances and driving skills, accident involvement and driving behaviour are examined using epidemiological data, injury and fatality statistics, empirical/behavioural evidence and survey research. Problems for the interpretation of such data are identified, and a number of questions remain unanswered for characterizing the magnitude and nature of the problem. Measures designed to counter the drugs and driving issue (e.g. secondary enforcement) are discussed. Proposals are made for further countermeasures based on current evidence.