The rules of the road
Although each state sets its own traffic laws, most laws are the same or similar throughout the country. Traffic is required to keep to the right, known as a right-hand traffic pattern. The exception is the US Virgin Islands, where people drive on the left.
Most states in the United States enforce priority to the right at uncontrolled intersections, where motorists must yield to the right.
The main US specificities compared to foreign rules includes some specific US rules:
- 4 stops with priority to the first vehicle
- Red light located after the junction rather than before
Speed limits are set by each state or territory, as well as counties or municipalities, on the roads within their jurisdiction. The maximum speed limit on rural two-lane roads ranges from 50 mph (80 km/h) in parts of the northeast to 75 mph (120 km/h) in parts of Texas. On rural Interstate Highways and other freeways, the speed limit ranges from 60 mph (96 km/h) in Hawaii to 85 mph (136 km/h) in parts of Texas. All roads in the United States have a speed limit, but it is not always posted (especially in rural areas).
Lane discipline and overtaking
Overtaking, usually called "passing", is legal on all four or more lane roads and on most two-lane roads with sufficient sight distance. On two-lane roads, one must pass to the left of the overtaken vehicle unless that vehicle is preparing to make a left turn, in which case the vehicle must be passed on the right. Passing on the left means that the overtaking vehicle must enter the oncoming lane. This should only be done in a legal passing zone, designated by either a dashed yellow center-line (indicating that passing is legal in both directions) or a solid line paired with a dashed line (indicating that passing is only legal for traffic adjacent to the broken line). A solid double yellow line indicated that passing is illegal in both directions.
Seat belt use
49 states and the District of Columbia have passed laws requiring seat belt use by at least all occupants of the front seat. New Hampshire is the only state with no such requirement for adults (anyone under eighteen must use a seat belt).
Drunk driving is the act of operating and/or driving a motor vehicle while under the influence of alcohol and/or drugs to the degree that mental and motor skills are impaired. It is illegal in all jurisdictions within the U.S. The specific criminal offense is usually called driving under the influence [of alcohol and/or other drugs] (DUI), and in some states driving while intoxicated (DWI), operating while impaired (OWI), or operating a vehicle under the influence (OVI). Such laws may also apply to boating or piloting aircraft. Vehicles can include farm machinery and horse-drawn carriages.
In the United States, the National Highway Traffic Safety Administration (NHTSA) estimates that 17,941 people died in 2006 in alcohol-related collisions, representing 40% of total traffic deaths in the United States. NHTSA states 275,000 were injured in alcohol-related accidents in 2003. The Bureau of Justice Statistics estimated that in 1996, local law enforcement agencies made 1,467,300 arrests nationwide for driving under the influence of alcohol, compared to 1,900,000 such arrests during the peak year in 1983. The arrest rate for alcohol-related offenses among American Indians was more than double that for the total population during 1996, and almost 4 in 10 American Indians held in local jails had been charged with a public order offense, most commonly driving while intoxicated. In 1997, an estimated 513,200 DWI offenders were under correctional supervision, down from 593,000 in 1990 and up from 270,100 in 1986. The most at risk are the younger people. In 2015, drivers with a BAC of 0.08% or higher are involved in a fatal crash; three in 10 were between 21 and 24 years old (28%).
NHTSA defines fatal collisions as "alcohol-related" if they believe the driver, a passenger, or non-motorist (such as a pedestrian or pedal cyclist) had a blood alcohol content (BAC) of 0.01 or greater. NHTSA defines nonfatal collisions as alcohol-related if the accident report indicates evidence of alcohol present. NHTSA specifically notes that alcohol-related does not necessarily mean a driver or non occupant was tested for alcohol and that the term does not indicate a collision or fatality was caused by the presence of alcohol. On average, about 60% of the BAC values are missing or unknown. To analyze what they believe is the complete data, statisticians simulate BAC information. Drivers with a BAC of 0.10 are 6 to 12 times more likely to get into a fatal crash or injury than drivers with no alcohol.
A driving license, typically called a "driver's license", is required to operate a motor vehicle on any public road in the United States. This license is issued by the authority of individual states (including Washington, D.C. and all territories). Drivers are normally required to obtain a license from their state of residence, and all states recognize each other's licenses for temporary visitors subject to normal age requirements. Most states allow people to drive unaccompanied once they have reached the age of sixteen. A state may suspend an individual's driving privilege within its borders for traffic violations. Many states share a common system of license classes, with some exceptions, and commercial license classes are standardized by the federal law of 49 CFR part 383.
When a driver is followed by a lighting police car, the driver should stop his/her car on the right and keep his/her hands on the wheel and keep his/her hands visible while not moving and not exiting of the vehicle.
For tourists, in case of accident it is preferable to call the police (911) rather than to help hurt people, and to stay in that place.
For some heavy vehicles, a Commercial driver's license is required, while a regular driver license is required for remaining vehicles.