Tiffini Diage
University of Wisconsin, Madison
Objective

Ignition Interlock Device (IID) sentencing,
impact on Wisconsin motor vehicle crashes?
 IID locks out vehicle ignition
○ Breath sample >0.02% BAC
○ Rolling re-test required
WI Alcohol Related MVC’s, 2007
17,847 people involved
 Injuries - 4,190

 Hospitalizations - 991
 ED visits - 3199
Deaths - 331
 50% were sober victims

*CODES Data provided by Wayne Bigelow; Center for Health Systems Research and Analysis,
University of Wisconsin – Madison
Proposed Wisconsin OWI Law

Mandatory IID Sentencing Requirements
 All repeat offenders (2nd offense or more)
 All 1st time offenders with BAC > 0.15

Offender pays $1,200 / device / year
Methods

Literature review – current evidence

Experience from other states

Impact analysis using Wisconsin data
Databases Reviewed, 2007
FARS
DUI
Related
Crashes
Drivers w/
Prior DUI
WI
DOT
2007 DUI
Convictions 1st
offense
2007 DUI
Convictions
2nd or repeat
offense
FARS = Fatal Accident Reporting System
WI DOT = Wisconsin Department of Transportation
Results

Literature evidence
 IID’s lower recidivism while device is
installed (Risk Ratio 0.05 – 0.33)
 Long-term effectiveness, uncertain

Experience from other states
 New Mexico
○ 85% reduction in recidivism
○ 25% reduction in alcohol related crashes
 California
○ Increase in non-alcohol related crashes with
IID users compared on non-IID users
Wisconsin Data, 2007

FARS – 142 fatal crashes
 30 with prior DUI’s (21%)
 27 were 1st offense, 3 were 2nd offense

CODES – 4,190 injuries
 No information on priors or BAC

WI DOT - 40,260 DUI convictions
 23,689 1st offenders (58%)
 16,571 2nd – 13th repeat offense (42%)
Findings

Impact of IID law on WI public health?
 Interaction with few fatal cases from 2007
 Large potential impact on repeat offenders

Low “in use” recidivism
 Decrease drunk driving exposure
 Reduction in risk of alcohol related crashes

Forward evaluation: IID data fields in
CODES and FARS
Discussion/Considerations
Political motivation vs. evidence based
intervention
 Ideology of policy based intervention?

 Punitive measure vs. prevention/treatment
 Could IID compliment treatment approach?

Proper evaluation is required for public
health assessment
 Effectiveness, unintended consequences
 Data communication – i.e. sentencing,
manufacturer, law enforcement
IID Data
Motor Vehicle
Crash Data
Acknowledgements
 Timothy
E. Corden, MD
 Steven Hargarten, MD
 Injury Research Center staff
 Sergeant William Brown, Milwaukee
Co. Sheriffs OWI Task Force Leader
 WI Department of Transportation staff
 Wayne Bigelow; Center for Health
Systems Research and Analysis,
University of Wisconsin – Madison