Effects of Washington State’s alcohol ignition interlock laws on DUI recidivism: An update

Objective: The objective of this study was to examine the effects of changes to Washington State’s alcohol ignition interlock laws: moving issuance of interlock orders from the courts to the driver licensing department (July 2003); extending the interlock order requirement to all persons convicted of driving under the influence (DUI; June 2004); allowing an interlock in lieu of an administrative driver’s license suspension (January 2009); and requiring proof of interlock installation to reinstate the driver’s license (January 2011). Method: Trends in conviction types, interlock installation rates, and 2-year cumulative recidivism rates were examined for first-time and repeat offenders with convictions stemming from DUI arrests during 1999–2012. Autoregressive integrated moving average (ARIMA) models examined the association between law changes and installation rates, law changes and recidivism rates, and installation rates and recidivism rates. Results: During the study period, there was a large increase in the proportion of first-time DUI arrests reduced to alcohol-related negligent/reckless driving convictions, offenses not requiring interlock orders. The interlock installation rate increased substantially and the recidivism rate declined substantially among both first and repeat offenders. Based on the ARIMA models for first offenders, the 2004 and 2009 law changes were associated with increased interlock installation rates and lower recidivism rates. For first offenders arrested during the last quarter of 2012, the model estimates a 26% reduction in the recidivism rate (from an expected 7.7% without the 4 laws to 5.6%). A 1 percentage point increase in the interlock installation rate was associated with a 0.06 percentage point decline in the recidivism rate among first offenders. If the association carried forward and if the installation rate had been 100% rather than 38% in the last quarter of 2012, the 2-year recidivism rate would have been reduced from 5.6 to 2%. Among repeat offenders, the 2003 and 2009 law changes were associated with increased interlock installation rates, and the 2009 law change was associated with a nonsignificant decline in recidivism. Conclusions: In Washington, rates of interlock installations increased as interlock laws were strengthened, and the increase was associated with reductions in recidivism among first DUI offenders. Washington’s experience suggests that states can reduce DUI recidivism by requiring interlock orders for all offenders, allowing offenders to install interlocks in lieu of an administrative driver’s license suspension, and closing statutory loopholes that allow plea reductions to convictions without interlock orders.研究目标：本研究旨在评估华盛顿州酒精点火联锁装置法规的修订效果，具体包含四项变更：2003年7月将联锁装置命令的签发权限从法院移交至机动车驾照管理部门；2004年6月将联锁装置命令的适用范围扩大至所有酒后驾驶（Driving Under the Influence，简称DUI）定罪人员；2009年1月允许以安装联锁装置替代行政驾照暂扣；2011年1月要求提供联锁装置安装证明方可恢复驾驶执照。 研究方法：本研究针对1999年至2012年间因酒后驾驶（DUI）被捕并定罪的初犯与再犯群体，分析了定罪类型、联锁装置安装率及2年累积再犯率的变化趋势。本研究采用自回归积分滑动平均（Autoregressive Integrated Moving Average，简称ARIMA）模型，分别检验法规变更与安装率、法规变更与再犯率、以及安装率与再犯率之间的关联。 研究结果：研究期间，因酒后驾驶（DUI）被捕后最终被降格判定为酒精相关过失驾驶/危险驾驶定罪（此类定罪无需执行联锁装置命令）的初犯占比大幅上升。初犯与再犯群体的联锁装置安装率均显著提升，而再犯率则显著下降。基于针对初犯群体的ARIMA模型分析结果，2004年与2009年的法规变更与联锁装置安装率提升及再犯率下降存在显著关联。针对2012年第四季度被捕的初犯群体，模型估算其再犯率较未实施四项法规变更的预期值（7.7%）下降26%，降至5.6%。初犯群体中，联锁装置安装率每提升1个百分点，再犯率即下降0.06个百分点。若该关联保持不变，且2012年第四季度的安装率从38%提升至100%，则2年累积再犯率将从5.6%进一步降至2%。针对再犯群体，2003年与2009年的法规变更与联锁装置安装率提升存在关联，而2009年的法规变更仅与再犯率的无统计学显著性下降相关。 研究结论：在美国华盛顿州，随着酒精点火联锁装置法规的不断强化，联锁装置安装率持续上升，且该上升趋势与初犯群体的再犯率下降存在显著关联。华盛顿州的实践经验表明，各州可通过以下举措降低酒后驾驶（DUI）再犯率：要求所有违法者执行联锁装置命令、允许违法者以安装联锁装置替代行政驾照暂扣，以及填补法定漏洞——此类漏洞允许违法者通过辩诉交易将定罪降格为无需执行联锁装置命令的罪名。