thumb|[[Policja officers conducting a traffic stop in Zabrze, Poland]]
A traffic stop, colloquially referred to as being pulled over, is a temporary detention of a driver of a vehicle and its occupants by police to investigate a possible crime or minor violation of law.
United States
thumb|A [[Los Angeles Police Department motor officer writing a traffic ticket for a motorist]]
A traffic stop is usually considered to be a Terry stop and, as such, is a seizure by police; the standard set by the United States Supreme Court in Terry v. Ohio regarding temporary detentions requires only reasonable articulable suspicion that a crime has occurred or is about to occur. Traffic stops can be initiated at any time during the detention and arrest process, ranging from stops prior to arrest or issuance of a ticket for violation based on probable cause.
Traffic stops date to the 1920s. Participation in "field sobriety tests" (FSTs or SFSTs) is voluntary in the U.S..
Probable cause
Probable cause is the arrest stage in which sufficient evidence is available to sustain a warrant for arrest. Probable cause is a stronger standard of evidence than a reasonable suspicion, but weaker than what is required to secure a criminal conviction. In some cases, notably DUI stops, the "sufficient evidence" is used for requiring an evidentiary chemical test (e.g., evidential breathalyzer test) by invoking an implied consent request. While state terminology regarding whether evidentiary testing is an "arrest", such testing is constitutionally a "search incident to arrest".
Procedure
thumb|An [[El Centro, California|El Centro Police Department officer conducting a traffic stop]]
A stop is usually accomplished through a process known as "pulling over" the suspect's vehicle. Police vehicles (except those used by undercover personnel) traditionally have sirens, loudspeakers, and lightbars that rotate or flash. These devices are used by the officer to get the attention of the suspect and to signal that they are expected to move over to the shoulder and stop. Failure to comply could result in citation of failure to yield to an emergency vehicle and possibly raise suspicion that the driver is attempting to flee.
Similar alerting devices are also typically equipped on other emergency vehicles such as fire trucks and ambulances, although police departments often use blue lights to signal drivers to pull over. In all cases, such signals and the laws requiring that other vehicles pull to the shoulder allow the emergency vehicles to pass other traffic safely and efficiently when responding to emergency situations. In the case of a traffic stop, the officer pulls the patrol vehicle behind the subject vehicle as it stops instead of proceeding past as they would during other emergency responses.
Depending upon the severity of the offense which the officer believes to have occurred, the officer may either arrest the suspect, by taking them to jail, or check for any outstanding warrants before issuing a citation also called a notice to appear or summons in some jurisdictions, which is essentially a traffic ticket. In some cases, officers may choose to simply issue a verbal or written warning.
If the driver is not the owner of the car, they are only penalized for the ticket. However, in most cases, the owner of the car that was stopped has increased insurances rates. This is due to a rule put in place to protect insurance companies from fraudulent procedures.
Many states have enacted laws requiring freeway traffic approaching the police vehicle to merge over to the left, leaving an entire lane as a buffer zone for the officer.
thumb|Los Angeles Police Department officers conducting a felony traffic stop
A "felony" or "high-risk" traffic stop occurs when police stop a vehicle which they have strong reason to believe contains a driver or passenger suspected of having committed a serious crime, especially of a nature that would lead the police to believe the suspects may be armed (such as an armed robbery, assault with a weapon, or an outstanding felony warrant for the registered owner). In a high risk stop, officers attempt to provide their own safety by issuing instructions to maintain absolute control over every step of the proceedings.
They will have additional officers on scene for back-up, often waiting for additional officers to join up before initiating the stop. They will typically have their weapons drawn, and stay back from the suspect's vehicle, using their patrol cars for cover. If there is no choice but to make the stop on a busy street, then they will often stop traffic. They will address the driver and any passengers over the PA speaker of the patrol car, typically instructing the driver to turn the engine off, remove the keys from the ignition, and sometimes toss them out the window. They will instruct the occupants, one at a time, to exit the vehicle with empty hands showing, place their hands on top of or behind their heads, walk backwards some distance, and then lie flat on the ground, where they will remain until all occupants have done likewise, at which point officers will move up, apply handcuffs, do a body search and then secure the suspects in the patrol cars. The vehicle is then typically searched for weapons and other evidence in accordance with the arresting department's standard operating procedures ("S.O.P.'s").
The Supreme Court has held that an officer who stops a vehicle as part of a routine traffic stop has the authority to order the driver to exit the vehicle, as well as to order any passengers to exit the vehicle.
Federal government
thumb|A [[Puerto Rico National Guard soldier assisting the Puerto Rico Police with a traffic stop, 2010. The National Guard was deployed to assist police while new police recruits were being trained.]]
The United States federal government has long used local traffic enforcement as a tool to further its goals through providing funding and training. Historically, this goal has been drug interdiction, but this has been expanded to include the war on terror. Currently, the National Highway Traffic Safety Administration (NHTSA) in cooperation with two agencies in the United States Department of Justice (the Bureau of Justice Assistance and the National Institute of Justice) actively promote a program called Data-Driven Approaches to Crime and Traffic Safety (DDACTS) which provides training to local police forces to combine traffic enforcement with fighting crime. In the past, such approaches have been accused of promoting racial profiling.
Federal grants to states often use the number of traffic tickets as a performance measure.
Controversy
Reducing minor traffic stops
Several states and cities have restricted or discouraged minor traffic stops, such as for broken equipment, to avoid dangerous interactions between drivers and armed law enforcement,
which put both police and drivers at risk
and lower trust in the police.
7% of killings by police started with a traffic stop. Two thirds of killings by police started with no crime or a nonviolent crime.
Jurisdictions can still use traffic cameras,
and can pull the car over and send a text message if both driver and police agency sign up for the service.
75% of police have not received recent hands-on training in removing a noncompliant person from a vehicle. Noncompliance was most common in cases of alcohol, drugs or illegal activity, and 42% of noncompliance involved disobeying the officer, while 24% involved not answering the officer' questions, a practice recommended by lawyers.
Some North Carolina cities encouraged drivers to refuse searches by requiring the officer to get a signed form, which clarified the voluntary nature of searches.
or supervisor pressure.
Illinois in 2016 found contraband in one stop per 242.
France, England and Wales use traffic stops at a quarter to a third of the US rate.
|colspan=5|Only stop for serious safety issues: unsafe speed, pedestrian right-of-way at crosswalks, failure to yield for turns, red light violations, stop sign violations, seatbelt violations, distracted driving (hands free law), DUI. || rear tag light out; taillights out in day; some but not all brake lights out||has rear tag but number not visible; no tag or expired less than 1 year|| small items on window or mirror which don't make crash more likely|| turn signal under 100' before turn; sleep in vehicle unless asked by another city agency|| any pedestrian stop unless immediate crash danger
|-
|Los Angeles City||CA
|colspan=5|(a) "minor equipment violations or other infractions" unless "officer believes" it "significantly interferes with public safety," or (b) "minor traffic or code violation" except if officer has information about a serious crime too
|-
|Lansing||MI||License plate lights out. For other lights out a stop is allowed to give the driver a coupon to pay for repair||Expired tabs [sic]|| Item dangling from the rearview mirror, unless that object impairs the driver’s ability to operate the vehicle safely|| ||
|-
|Ramsey County||MN|| || || || ||
|-
|Mecklenburg County||NC|| || || || ||
|-
|All state||OR||1 headlight, taillight or brake light, non-red taillight, license plate light|| || || ||
|-
|Philadelphia, may mail citation or warning.||PA ||1 light out||temporary registration visible but wrong place, lack inspection or emission sticker, registration up to 2 months late or loose||item obstructing driver's view||missing bumper||
|-
|Pittsburgh||PA||one light out||registration up to 2 months late or not secure, temporary registration shown in wrong place|| || bumper loose||
|-
|All state||VA||unapproved unsafe light, signal or glass, tail lights, license plate lights, brake lights if 1 works, 1 headlight||registration or inspection up to 4 months late||window tints, items blocking driver's view||noisy exhaust, marijuana odor, local vehicle ordinances unless jailable||jaywalking
|-
|All state||VT
|colspan=5|Reports required by January & October 2023
|-
|Chittenden County||VT|| || || || ||
|-
|}
Racial disparities
Stanford has compiled data on race of drivers stopped in 200 million traffic stops.
Stops are particularly common and harmful for minorities.
California's annual report under the Racial and Identity Profiling Act (RIPA) highlights that minorities form a bigger share of traffic stops than their share of the residents in each area.
Several organizations have commented that comparing minority share of traffic stops to resident population is an erroneous approach, and that there are other possible comparisons, including: driving age population, traffic accidents, licensed drivers, traffic violators, arrests, and crime suspects.
The New Mexico Sentencing Commission in 2007 called the use of Census data on residents a "common, but very poor method," and listed other methods.
A 2006 report from the US Department of Justice shows the different comparison groups used by studies up to that point.
A 2023 study for the Peace Officers Research Association of California (PORAC) listed some of the same alternative comparison groups: licensed drivers, vehicle owners, center city populations, field studies, and traffic violators.
There is another way comparative reports underestimate the number of Black drivers. Typically statistics on residents call them Black only if they are not Hispanic, and are not mixed race. Mixed race and Hispanic residents are counted separately.
Police will count people stopped as Black even if they are also Hispanic or are also of another race. (RIPA shows that police rarely classify drivers as multi-racial.
Exemptions for police friends, families and contacts
Several police unions print cards for members to give to friends, family members, and professional contacts. Officers who make a traffic stop and are shown the card are under pressure to let the holder off with a warning instead of a ticket. The pressure can be from fellow officers Los Angeles and Philadelphia. Cards were a "time-honored" tradition in Los Angeles by 1923 despite efforts by the police chief and a city councilman to stop them. The California Highway Patrol gave cards under Chief Cato, appointed in 1931.
The cards have a racial effect, since police are disproportionately white. The cards go to whites disproportionately, including as Christmas gifts, 20-30 have been given to each police officer each year, and 10-20 to each retired officer, so they have also been available on auction sites for up to $200.