Traffic & Driving Law
Learn about vehicle codes, traffic citations, driver license suspensions, DUI/DWI legal thresholds, and administrative hearings.
Traffic and motor vehicle codes are entirely state-specific. Penalties, point systems, and DUI administrative procedures differ by state jurisdiction.
Understanding Traffic & Driving Law in the United States
Traffic and driving law encompasses the statutes, administrative codes, and municipal ordinances regulating the operation of motor vehicles on public roadways. Primarily governed at the state level through motor vehicle codes (administered by state DMVs or BMVs), traffic law distinguishes between civil infractions (speeding, parking) and criminal traffic offenses (DUI/DWI, reckless driving, vehicular homicide).
Primary Governing Authorities in Traffic & Driving Law
Uniform Vehicle Code (UVC)
Model statutory code adopted in varying degrees across all 50 states to standardize traffic rules.
National Highway Traffic Safety Administration (NHTSA)
Federal agency setting vehicle safety standards, highway safety grants, and DUI prevention guidelines.
Driver License Compact (DLC)
Interstate agreement where 45 states share traffic conviction and license suspension data.
Key Legal Scenarios & Decision Thresholds
What is the difference between a traffic infraction and a misdemeanor traffic crime?
Infractions are civil violations resulting in fines and license points; misdemeanors (DUI, reckless driving) carry criminal records and potential jail.
How do implied consent laws apply to DUI breathalyzer tests?
By driving on public roads, drivers automatically consent to chemical testing if lawfully arrested for DUI; refusing leads to automatic license suspension.
How does the Driver License Compact affect out-of-state traffic tickets?
45 states exchange traffic ticket information; violations committed out-of-state are treated as if they occurred in your home state.
In-Depth Legal Guides in Traffic & Driving Law
New guides for Traffic & Driving Law are currently in editorial review.
Frequently Asked Questions in Traffic & Driving Law
Can I fight a speeding ticket in traffic court?
Yes. Drivers can contest speeding citations by challenging radar calibration records, officer visual estimation, or presenting emergency defense evidence.
What is the blood alcohol concentration (BAC) legal limit in the U.S.?
In 49 states, the per se legal limit for non-commercial adult drivers is 0.08% BAC. Utah is the sole state with a lower threshold of 0.05% BAC.
How do points on your driving license work?
State DMVs assign point values to moving violations. Accumulating too many points within a 12 to 24-month period results in mandatory license suspension.