Monitoring Technology


This is the last of six videos produced by the National Center for State Courts and ABA Judicial Outreach Liaisons, supported by NHTSA, about issues in traffic adjudication. In this video, judges discuss the latest developments in DWI offender monitoring technology, such as ignition interlocks and transdermal alcohol monitoring systems.

Related Resources

Ignition Interlock Report, NCSC (2018). This report reviews the latest research on ignition interlock programs and how they are used from a national perspective (2013-2017). The appendix contains a detailed chart of each state’s ignition interlock program and a comprehensive resource list. 

2016 Annual Ignition Interlock Survey: United States, Traffic Injury Research Foundation USA, Inc. (May 2017). This is TIRF’s annual update on the state of ignition interlock laws and enforcement in the United States. The report analyzes traffic crash and the changes in that data from year-to-year, and it provides information about new legislation and policies implemented from state to state.

Interlock Data UtilizationNHTSA (August 2017). This report summarizes findings on ignition interlock data that is used for DWI offender monitoring and offender-related programs such as screening, assessments, and treatment for alcohol abuse problems. It describes the uses of interlock data, procedures for using interlock data, and challenges and issues related to using interlock data.

Mandating Treatment Based on Interlock Performance: Evidence for EffectivenessAlcoholism: Clinical and Experimental Research (September 2016). This study used Florida interlock data to analyze the success of combining alcohol use disorder treatment with interlock data. The study found that individuals who received AUD treatment after a certain number of interlock violations were statistically less likely to reoffend following the removal of the ignition interlock. The study estimated that the decline in recidivism prevented a measurable number of rearrests, crashes, and traffic injuries.

Impact of State Ignition Interlock Laws on Alcohol-Involved Crash Deaths in the United StatesAmerican Journal of Public Health(May 2016). This study analyzed NHTSA crash data from 1999 to 2013 and compared alcohol-involved crash deaths between states with and without interlock requirements. The study found that requiring ignition interlocks for all impaired driving convictions led to 15% fewer alcohol-involved crash deaths. The study recommended wider use for interlocks.

Evaluation of State Ignition Interlock Programs: Interlock Use Analyses From 28 States, 2006–2011NHTSA (2015). This NHTSA study evaluated ignition interlock data from just over half of the states in the United States. The study concluded that requirements and incentives had the strongest positive relationship to higher interlock use rates, while monitoring, coordination, uniformity, and education were moderately to strongly related to higher interlock use rates.

Transdermal Alcohol Monitoring: Case StudiesNHTSA (2012).  This study surveys the use of transdermal alcohol monitoring as used in a wide variety of programs nationally.

Evaluating Transdermal Alcohol Measuring DevicesNHTSA (2007). This report is an evaluation study of two types of transdermal devices that detect alcohol at the skin surface representing two types of electrochemical sensing technology: the AMS SCRAM™ ankle device and the Giner WrisTAS™ wrist device. The report summarizes comments from research subjects, offenders, and vendors who manage transdermal detection programs.