An analysis of drug recognition expert evaluations and comparisons with police issued citations in Maryland, 2017–2021

Drug Recognition Expert (DRE) officers utilize standardized evaluations to assess physiological and behavioral indicators of drug impairment. This study analyzed data from Maryland DRE officers (2017–2021), comparing their drug category/ies assessments with blood tests results. DRE evaluation records were linked to citations issued for alcohol/drug-impaired driving, to examine the agreement between charges, DRE evaluation, arrest outcomes, and repeat offenses. Data from 4,931 DRE evaluations were analyzed, involving 4,727 drivers linked to citation records for alcohol/drug-impaired driving offenses. Agreement between DRE opinions and blood test results was quantified by estimating binomial success probabilities with 95% confidence intervals. Citation outcomes and repeat offense rates for DRE and non-DRE cases were also presented. Of 4,931 unique evaluations, blood specimens were collected in 2,118 (42.9%), yielding 1,599 positive drug test results (75.5%). Most evaluated drivers were white (67.6%), male (73.8%), and aged 21–34 years (43.2%). Comparison of DRE opinion with blood test results revealed an overall success probability of 84.2 ± 0.65%. DRE accuracy improved to 91.8 ± 0.85% when none or one drug was detected and decreased to 80.5 ± 0.87% when two or more drugs were involved. When linked to citation data, 3,237 drivers (68.5%) received 36,878 citations, with 88.1% having two or more drug-related offenses and 72.5% having at least one negligent driving offense. Matched DRE drivers were involved in 9,105 traffic stops, with approximately 48.4% receiving over five citations during their first stop. 97.3% were cited for drug impairment, with only 87 drivers avoiding such citations. This study highlights the effectiveness of the DRE program in identifying impaired drivers, providing insights into driver demographics and impairment patterns, while emphasizing need for improved polysubstance impairment data collection. A high degree of agreement between DRE opinions and blood test results for all tested drug categories were statistically established. Despite the program’s success, significant gaps remain in testing methods and integrating alcohol and drug evaluations. Future research should enhance testing protocols, expanding data collection, and examining the link between substance use disorders and impaired driving to strengthen prevention, enforcement, and intervention efforts.

药物识别专家（Drug Recognition Expert，DRE）警官采用标准化评估方法，评估药物损伤的生理与行为指标。本研究分析了马里兰州DRE警官2017-2021年的数据，将其对药物类别（单类或多类）的评估结果与血液检测结果进行对比。研究将DRE评估记录与酒精/药物影响驾驶的罚单数据关联，以分析指控、DRE评估、逮捕结果及重复违规行为之间的一致性。共分析4931份DRE评估数据，涉及4727名与酒精/药物影响驾驶违规罚单记录相关联的驾驶员。DRE评估意见与血液检测结果的一致性通过估算二项成功概率（binomial success probability）及95%置信区间（confidence interval）进行量化。同时呈现了DRE与非DRE案例的罚单结果及重复违规率。在4931份独立评估中，2118份（42.9%）采集了血液样本，其中1599份（75.5%）药物检测结果呈阳性。接受评估的驾驶员中，多数为白人（67.6%）、男性（73.8%），年龄介于21-34岁（43.2%）。DRE评估意见与血液检测结果的对比显示，总体成功概率为84.2±0.65%。当检测到零种或一种药物时，DRE准确率提升至91.8±0.85%；而涉及两种及以上药物时，准确率降至80.5±0.87%。关联罚单数据后发现，3237名驾驶员（68.5%）共收到36878张罚单，其中88.1%存在两次及以上药物相关违规，72.5%至少有一次疏忽驾驶违规。匹配的DRE相关驾驶员涉及9105次交通拦截，约48.4%的驾驶员在首次拦截时收到超过5张罚单。97.3%的驾驶员因药物损伤被开罚单，仅87名驾驶员未被此类罚单记录。本研究凸显了DRE项目在识别受影响驾驶员方面的有效性，为驾驶员人口统计学特征及损伤模式提供了洞见，同时强调需改进多物质损伤（polysubstance impairment）的数据收集。统计分析证实，DRE评估意见与所有检测药物类别的血液检测结果之间存在高度一致性。尽管该项目成效显著，但检测方法及酒精与药物评估的整合方面仍存在显著差距。未来研究应优化检测协议、扩大数据收集范围，并探究物质使用障碍（substance use disorder）与受影响驾驶之间的关联，以强化预防、执法及干预措施。