Intervention Glossary

Name of Intervention
(Short Name)
Automated red-light camera enforcement
(red-light camera)
Commonly called red-light cameras, automated red-light camera enforcement is used to capture an image of a vehicle whose driver fails to stop for a red light. Tickets are generally sent to offenders by mail.
Automated speed-camera enforcement
(speed camera)
Commonly called speed cameras, automated speed-camera enforcement captures an image of a vehicle whose driver is driving in excess of the posted speed limit. Unlike red-light cameras, which are deployed only at intersections, mobile speed cameras are often used to cover multiple road segments.
Alcohol interlocks Alcohol interlocks, also called ignition interlocks, are devices that prevent a vehicle from starting until the driver has blown into a tube and determined that his or her BAC is below the allowable level set by the state (0.02 in most jurisdictions). This intervention calls for interlocks to be installed on the vehicles of all DWI offenders, including first-time offenders.
Sobriety checkpoints At a sobriety checkpoint, teams of police officers stop cars at a specific location to check drivers for alcohol levels. States generally publicize such events to discourage drivers from drinking, particularly during times when drunk driving is more common than usual (such as holiday weekends).
Saturation patrols Saturation patrols consist of an increased police presence in selected locations where they patrol the area looking for suspicious driving behavior. In contrast to sobriety checkpoints, they do not stop every vehicle.
Bicycle helmet laws for children
(bicycle helmet)
To reduce the likelihood of trauma to the head and its related consequences, bicycle helmet laws mandate the use of helmets by children while they are riding bicycles.
Universal motorcycle helmet laws
(motorcycle helmet)
This law requires all motorcyclists, regardless of age or experience level, to wear a helmet the meets safety standards set by DOT. These laws contrast with partial helmet laws, which typically apply only to riders below a certain age.
Primary enforcement of seat belt laws
(primary enforcement of seat belt laws)
States with seat belt laws vary in their enforcement. A primary law allows police to ticket an offender exclusively for not wearing a seat belt. A secondary law allows police to write a ticket for not wearing a seat belt only if the driver has been pulled over for a different offense.
High-visibility enforcement for seat belts and child restraint laws
(seat belt enforcement campaign)
High-visibility enforcement is a technique that combines intense enforcement over a fixed period (for example, one or two weeks) with a publicity campaign. A campaign focused on restraint use generally includes all forms of restraints: seat belts and child restraints (child safety seats and booster seats).
License plate impoundment This intervention requires a driver who has been convicted of DWI to surrender the vehicle’s license plate, which is either impounded or destroyed. In some jurisdictions, the license plate is not physically removed; rather, officers place stickers on the license plate to indicate that it is invalid. The stickers are designed so that, if someone tries to remove them, they leave a visible pattern on the plate. Because it is relatively easy for police to observe whether a vehicle has a license plate or the stickers, this intervention deters convicted DWI offenders from driving that vehicle.
Limits on diversion and plea agreements
(limits on diversion)
Although all states have penalties for DWI, many states have additional programs that allow some offenders to be diverted out of the normal procedures or to plead guilty to a lesser offense and receive a lighter sanction. These programs are most often targeted at first-time offenders, with the goal of reducing the DWI case load by diverting people who are thought to be unlikely to reoffend. Limits on diversion and plea agreements would increase the number of DWI arrestees convicted of more-serious DWI-related charges.
Vehicle impoundment This intervention results in the vehicle of a DWI offender being confiscated for a period of time and stored in a public impound lot. An offender can either reclaim or surrender his or her vehicle when the impoundment period ends.
In-person license renewal This intervention requires all drivers over age 70 to renew their driver’s licenses in person at a department of motor vehicles instead of using mail-in or online renewal.
Higher seat belt fines This intervention adds $75 to a state’s existing fine, which represents a significant increase over existing seat belt fines in most states.

SOURCES: Effectiveness and use ratings from UNC Highway Safety Research Center, 2011; Goodwin, Kirley, et al., 2013.

NOTE: BAC = blood alcohol concentration. DWI = driving while intoxicated. DOT = U.S. Department of Transportation. State terminology varies; a DWI charge against a drunk driver is the same as a charge of driving under the influence (DUI). For the sake of consistency, this report uses DWI. The short name is the same as the intervention name in the tool.