Editing Traffic stop (section)

==Controversy==

===Reducing minor traffic stops===
{{see|Driving while black}}
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,<ref name="marshall">{{Cite web |last=Lartey |first=Jamiles |date=2023-02-11 |title=How Police Traffic Stops May Change After Tyre Nichols' Death |url=https://www.themarshallproject.org/2023/02/11/police-tyre-nichols-traffic-stop |access-date=2023-02-24 |website=The Marshall Project |language=en}}</ref><ref name="pew">{{Cite web |last=Mercer |first=Marsha |date=2020-09-03 |title=Police 'Pretext' Traffic Stops Need to End, Some Lawmakers Say |url=https://pew.org/3gToNRD |access-date=2023-02-07 |website=pew.org |language=en}}</ref>
which put both police and drivers at risk<ref name="chapman">{{Cite web |last=Chapman |first=Steve |date=2017-07-20 |title=Curbing Traffic Stops Would Save Lives |url=https://reason.com/2017/07/20/curbing-traffic-stops-would-save-lives/ |access-date=2023-02-07 |website=Reason.com |language=en-US}}</ref>
and lower trust in the police.<ref name="marshall"/>
Nationally, 43% of traffic stops are for speeding, 24% for broken equipment, and 9% for suspected criminal activity.<ref name="rand"/> 730 police killings from 2017 to 2022 started with traffic stops.<ref name="moreno">{{Cite news |last=Moreno-Rivera |first=Finesse |date=2022-11-30 |title=Police kill far too many people during traffic stops. We must change why stops are made. |language=en-US |work=USA Today |url=https://www.usatoday.com/story/opinion/policing/2022/11/20/police-killings-no-decline-despite-reforms-george-floyd/10648861002/ |access-date=2023-05-02}}</ref>
7% of killings by police started with a traffic stop. Two thirds of killings by police started with no crime or a nonviolent crime.<ref name="mpv">{{Cite web |title=Mapping Police Violence |url=https://mappingpoliceviolence.us/ |access-date=2023-02-24 |website=Mapping Police Violence |language=en-US}}</ref>

Jurisdictions can still use traffic cameras,<ref name="chapman"/>
send tickets in the mail<ref name="vera">{{Cite web |last=Dholakia  |first=Nazish, and Akhi Johnson  |date=2022-02-09 |title=Low-Level Traffic Stops Too Often Turn Deadly. Some Places Are Trying… |url=https://www.vera.org/news/low-level-traffic-stops-too-often-turn-deadly-some-places-are-trying-to-change-that |access-date=2023-02-07 |website=Vera Institute of Justice |language=en-US}}</ref><ref name="lof22">P. 24: "mailing warnings or citations to the registered owner of the vehicle." {{Cite web |last=Lofstrom |first=Magnus, Joseph Hayes, Brandon Martin, and Deepak Premkumar  |date=2022-10-05 |title=Racial Disparities in Traffic Stops |url=https://www.ppic.org/publication/racial-disparities-in-traffic-stops/ |access-date=2023-08-04 |website=Public Policy Institute of California |language=en-US}}</ref>
and can pull the car over and send a text message if both driver and police agency sign up for the service.<ref name="kxan">{{Cite web |date=2023-01-20 |title=New policing tool could eliminate the need for some traffic stops |url=https://www.kxan.com/news/texas/new-policing-tool-could-eliminate-the-need-for-some-traffic-stops/ |access-date=2023-02-24 |website=KXAN Austin |language=en-US}}</ref>

75% of police have not received recent hands-on training in removing a noncompliant person from a vehicle.<ref name="rand">{{Cite web |last=Harrison |first=Bob |date=2021-06-30 |title=Stop, Start, or Continue? A National Survey of the Police About Traffic Stops |url=https://www.rand.org/blog/2021/06/stop-start-or-continue-a-national-survey-of-the-police.html |access-date=2023-02-07 |website=www.rand.org |language=en}}</ref> 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.<ref name="aclu">{{Cite web |date=2012-06-05 |title=Dealing with Law Enforcement |url=https://www.aclusocal.org/en/dealing-law-enforcement |access-date=2023-02-07 |website=ACLU of Southern California |language=en}}</ref>
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.<ref name="tcr"/>

Some departments have quotas for at least a minimum number of traffic stops per officer per month,<ref name="banner">{{Cite web |last=Conarck |first=Ben |date=2023-02-08 |title=Leaked docs: State police use quota-like system to reward arrests |url=https://www.thebaltimorebanner.com/community/criminal-justice/maryland-state-police-quota-points-system-leaked-documents-WAGOQ4PLVFBJVEZIUJXUZUBB7Q/ |access-date=2023-02-24 |website=the-baltimore-banner |language=en}}</ref>
or supervisor pressure.<ref name="bbc">{{Cite web |last=Debusmann |first=Bernd  |date=2023-01-31 |title=Why do so many police traffic stops turn deadly? |url=https://www.bbc.com/news/world-us-canada-64458041 |access-date=2023-02-24 |website=BBC News |language=en-GB}}</ref>

Illinois in 2016 found contraband in one stop per 242.<ref name="chapman"/>
In July 2021 a study found that [[State patrol]] traffic stops were not associated with reduced motor vehicle crash deaths and suggested other strategies such as motor vehicle modifications, community-based safety initiatives, improved access to health care, or prioritizing [[trauma care]] as other reduction efforts. <ref>{{Cite journal|last1=Sarode|first1=Anuja L.|last2=Ho|first2=Vanessa P.|last3=Chen|first3=Lin|last4=Bachman|first4=Katelynn C.|last5=Linden|first5=Philip A.|last6=Lasinski|first6=Alaina M.|last7=Moorman|first7=Matthew L.|last8=Towe|first8=Christopher W.|date=2021-07-01|title=Traffic stops do not prevent traffic deaths|journal=The Journal of Trauma and Acute Care Surgery|volume=91|issue=1|pages=141–147|doi=10.1097/TA.0000000000003163|issn=2163-0763|pmid=34144561|pmc=8900371 |s2cid=233704108}}</ref>
France, England and Wales use traffic stops at a quarter to a third of the US rate.<ref name="chapman"/>

====Table of state and local practices====

{|class="wikitable sortable" style="font-size: 75%; text-align: center; width: auto;"
|+Reasons which do not justify a traffic stop
|-
!Jurisdiction||State||Lights||Tags & stickers||Blocked view||Other||Pedestrian
|-
|Berkeley||CA<ref name="kirk">{{Cite web |last1=Kirkpatrick |first1=David D. |last2=Eder |first2=Steve |last3=Barker |first3=Kim |date=2022-04-15 |title=Cities Try to Turn the Tide on Police Traffic Stops |url=https://www.nytimes.com/2022/04/15/us/police-traffic-stops.html |access-date=2023-02-07 |website=The New York Times |language=en-US}}</ref>
|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.<ref name="ripapp"/>
|-
|San Francisco City/County (subject to union negotiation)<ref name="holder"/>||CA<ref name="dickey">{{Cite web |last=Dickey |first=Megan Rose |date=2023-01-13 |title=San Francisco Police Commission votes to restrict low-level traffic stops |url=https://www.axios.com/local/san-francisco/2023/01/13/low-level-traffic-stops-restriction-san-francisco-police |access-date=2023-02-07 |website=Axios |language=en}}</ref><ref name="sf9">{{Cite web |last=San Francisco Police Department |date=2023-01-11 |title=CURTAILING THE USE OF PRETEXT STOPS |url=https://sf.gov/sites/default/files/2023-01/PoliceCommission11123-DGO%209.07_12.28.22_CLEAN.pdf |website=San Francisco}}</ref> || 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<ref name="kirk"/><ref name="jany">{{Cite web |last=JANY |first=LIBOR, and BEN POSTON |date=2022-11-14 |title=Minor police encounters plummet after LAPD put limits on stopping drivers and pedestrians |url=https://www.latimes.com/california/story/2022-11-14/minor-traffic-stops-plummet-in-months-after-lapd-policy-change |access-date=2023-02-07 |website=Los Angeles Times |language=en-US}}</ref>
|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<ref name="lam">{{Cite web |last=Chief of Police |date=2022-03-01 |title=Department Manual Section 1/240.06, Policy - Limitation on Use of Pretextual Stops |url=http://www.lapdpolicecom.lacity.org/030122/BPC_22-042.pdf |website=Los Angeles City Police Commission}}</ref>
|-
|Lansing||MI<ref name="kirk"/><ref name="ripapp"/>||license plate light out, cracked taillights|| ||dangling ornaments, and window treatments||regulatory violations such as, cracked windshields, loud exhaust||
|-
|Brooklyn Center||MN<ref name="kirk"/>
|colspan=5|No immediate end to traffic stops, and issuing citations. Policy "prohibiting custodial arrests or consent searches of persons or vehicles, for any non-moving traffic infraction, non-felony offense, or non-felony warrant, unless otherwise required by law"<ref name="ripapp"/>
|-
|Minneapolis||MN<ref name="ripapp"/><ref name="mnpol">{{Cite web |date=2021-10-08 |title=Minneapolis Police Policy and Procedure Manual, Section 7-604 Traffic |url=https://www.minneapolismn.gov/media/-www-content-assets/documents/MPD-Policy-and-Procedure-Manual.pdf |access-date=2023-08-03 |website=Minneapolis City Government}}</ref>||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<ref name="vera"/>|| || || || ||
|-
|Fayetteville||NC<ref name="jallow">{{Cite web |last=Jallow |first=Ahmed |date=2022-03-21 |title=Taking cops out of traffic stops: Would it make a difference? North Carolina examples offer a clue |url=https://www.thetimesnews.com/in-depth/news/2021/03/22/police-reform-fayetteville-burlington-nc-traffic-stops-policing/4622232001/ |access-date=2023-02-07 |website=www.thetimesnews.com |language=en}}</ref>|| || || || ||
|-
|Mecklenburg County||NC<ref name="white">{{Cite web |last=White |first=Herbert |date=2022-10-02 |title=Mecklenburg County Sheriff's Office ends administrative traffic stops |url=https://www.thecharlottepost.com/news/2022/10/02/local-state/mecklenburg-sheriff-s-office-ends-traffic-stops-for-administrative-violations/ |access-date=2023-02-07 |website=www.thecharlottepost.com |language=en-US}}</ref>|| || || || ||
|-
|All state||OR<ref name="or">{{Cite web |date=2022-03-04 |title=SB1510 2022 Regular Session - Oregon Legislative Information System |url=https://olis.oregonlegislature.gov/liz/2022R1/Measures/Analysis/SB1510 |access-date=2023-02-24 |website=olis.oregonlegislature.gov}}</ref>||1 headlight, taillight or brake light, non-red taillight, license plate light|| || || ||
|-
|Philadelphia, may mail citation or warning.||PA<ref name="kirk"/><ref name="ripapp"/><ref name="holder">{{Cite web |last=Holder |first=Sarah |date=2023-02-02 |title=These Cities Are Limiting Traffic Stops for Minor Offenses |url=https://www.bloomberg.com/news/articles/2023-02-02/police-traffic-stops-face-new-scrutiny-after-tyre-nichols-death |access-date=2023-02-07 |website=Bloomberg.com |language=en}}</ref> ||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<ref name="kirk"/> 
|colspan=5| same as Philadelphia,<ref name="ripapp"/> police not following limits<ref name="holder"/>
|-
|Memphis||TN<ref name="burgess">{{Cite news |last=Burgess |first=Katherine, and Lucas Finton |date=2023-04-11 |title=Memphis passes 'Achieving Driving Equality' ordinance after Tyre Nichols' death |language=en-US |work=Commercial Appeal |url=https://www.commercialappeal.com/story/news/politics/2023/04/11/memphis-passes-achieving-driving-equality-after-tyre-nichols-death/70099925007/ |access-date=2023-05-02}}</ref>||one light out||registration up to 2 months late or not secure, temporary registration shown in wrong place|| || bumper loose||
|-
|All state||VA<ref name="kirk"/><ref name="valis">{{Cite web |date=2020-11-09 |title=Bill Tracking - 2020 session > Legislation, H5068 |url=https://lis.virginia.gov/cgi-bin/legp604.exe?202+ful+CHAP0045 |access-date=2023-08-04 |website=Virginia Legislative Information System}}</ref>||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<ref name="vt23a">{{Cite web |date=2023-01-15 |title=REPORT TO THE VERMONT LEGISLATURE In Accordance with Act 106 (2022), Relating to Secondary Enforcement of Minor Traffic Offenses. |url=https://legislature.vt.gov/Documents/2024/WorkGroups/House%20Transportation/Reports%20and%20Resources/W~Agency%20of%20Transportation~An%20Act%20Relating%20to%20Secondary%20Enforcement%20of%20Minor%20Traffic%20Offenses~1-13-2023.pdf |access-date=2023-08-03 |website=Vermont Legislature}}</ref> & October 2023<ref name="vt22">{{Cite web |date=2022-05-09 |title=H.635 (Act 106), An act relating to secondary enforcement of minor traffic offenses |url=https://legislature.vermont.gov/Documents/2022/Docs/ACTS/ACT106/ACT106%20As%20Enacted.pdf |access-date=2023-08-03 |website=Vermont General Assembly}}</ref>
|-
|Chittenden County||VT<ref name="vera"/>|| || || || ||
|-
|Seattle||WA<ref name="kirk"/><ref name="green">{{Cite web |last=Green |first=Sara Jean |date=2022-01-18 |title=Seattle Police will no longer enforce some minor traffic violations |url=https://www.police1.com/patrol-issues/articles/seattle-police-will-no-longer-enforce-some-minor-traffic-violations-AtJzjC7QPYhEiVdC/ |access-date=2023-02-07 |website=Police1 & Seattle Times |language=en}}</ref>|| || || || ||
|-
|}

===Racial disparities===
Stanford has compiled data on race of drivers stopped in 200 million traffic stops.<ref name="stan">{{Cite web |title=The Stanford Open Policing Project |url=https://openpolicing.stanford.edu/ |access-date=2023-02-07 |website=openpolicing.stanford.edu}}</ref>
Stops are particularly common and harmful for minorities.<ref name="tcr">{{Cite web |date=2018-07-17 |title=Why Traffic Stops Don't Stop Crime |url=https://thecrimereport.org/2018/07/17/why-traffic-stops-dont-stop-crime/ |access-date=2023-02-07 |website=The Crime Report |language=en-US}}</ref>
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.<ref name="ripa">{{Cite web |title=RIPA Board Reports |url=https://oag.ca.gov/ab953/board/reports |access-date=2023-08-03 |website=State of California - Department of Justice - Office of the Attorney General |date=28 December 2018 |language=en}}</ref>

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.<ref name="ojp6"/> On average, minorities work more jobs and work from home less than non-minorities, so are on the road more than their share of the residential population. Also, police are called by people in minority neighborhoods more than elsewhere, so police are in a position to see more traffic violations there.<ref name="nij13">{{Cite web |date=2013-01-09 |title=Racial Profiling and Traffic Stops |url=https://nij.ojp.gov/topics/articles/racial-profiling-and-traffic-stops |access-date=2023-08-03 |website=National Institute of Justice |language=en}}</ref>
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.<ref name="nm7">{{Cite web |date=September 2007 |title=Bias-Based Policing: a Literature Review |url=https://isr.unm.edu/reports/2007/Bias%20Based%20Lit%20Review.pdf |website=New Mexico Sentencing Commission}}</ref>
A 2006 report from the US Department of Justice shows the different comparison groups used by studies up to that point.<ref name="ojp6">Table 4.9 on p.123,  discussed on pp.30-31. {{Cite web |last=McMahon  |first= Joyce; Joel Garner; Ronald Davis; Amanda Kraus  |date=July 2006|title=How to Correctly Collect and Analyze Racial Profiling Data: Your Reputation Depends On It!  |url=https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=3cf46e7dd9bbf5a2f2799104e4f782684e0a1e2b |access-date=2023-08-03 |website=Office of Justice Programs, US Department of Justice}}</ref> 
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.<ref name="porac23">{{Cite web |last=Withrow |first=Brian L.  |date=2023-01-02 |title=Racial & Identity Profiling Advisory Board 2022 Annual Report, A Critical Analysis |url=https://porac.org/wp-content/uploads/PORAC-2022-RIPA-Report-Analysis_FINAL.pdf |website=Peace Officers Research Association of California (PORAC)}}</ref>

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.<ref name="ripapp">{{Cite web |date=2023-01-01 |title=RIPA Appendix 2023 |url=https://oag.ca.gov/system/files/media/ripa-appendix-2023.pdf |access-date=2023-08-03 |website=State of California - Department of Justice - Office of the Attorney General |language=en}}</ref> 
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.<ref name="ripa"/>) So the comparison of traffic stops underestimates the number of Blacks in the resident population and overestimates Blacks among the people stopped.

A Connecticut investigation found that 26,000 traffic tickets reported by state police did not appear in court records. The researchers hypothesized that state police were trying to look productive. The fake stops were disproportionately white, reducing apparent racial gaps. The police union said data entry errors were the likely cause.<ref name="ct">{{Cite news |last=Nierenberg |first=Amelia |date=2023-09-04 |title=Over 100 Connecticut state troopers accused of faking traffic stops |language=en-US |work=Boston Globe |url=https://www.boston.com/news/national-news/2023/09/04/over-100-connecticut-state-troopers-accused-of-faking-traffic-stops/ |access-date=2023-09-13}}</ref>

===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.<ref name="way">{{Cite news |last=Way |first=Katie |date=2020-09-02 |title=The Little Cards That Tell Police 'Let's Forget This Ever Happened' |language=en |work=Vice |url=https://www.vice.com/en/article/pba-card-police-courtesy-cards/ |access-date=2023-06-05}}</ref><ref name="helmore">{{Cite news |last=Helmore |first=Edward |date=2023-06-04 |title=Traffic cop sues city over 'get-out-of-jail-free' cards for NYPD friends and family |language=en-GB |work=The Guardian |url=https://www.theguardian.com/us-news/2023/jun/04/nypd-lawsuit-courtesy-cards-traffic-tickets |access-date=2023-06-05 |issn=0261-3077}}</ref> The pressure can be from fellow officers<ref name="way"/> and supervisors.<ref name="helmore"/> 

The cards have been issued in New York City, New Jersey,<ref name="way"/> Boston,<ref name="sanok">{{Cite news |last=Sanok |first=Ann |date=2007-07-06 |title=Recreation struggles to survive |language=en-US |work=South Coast Today |url=https://www.southcoasttoday.com/story/news/2007/07/06/recreation-struggles-to-survive/52857625007/ |access-date=2023-06-05}}</ref> Los Angeles<ref name="grace">{{Cite news |last=Grace |first=Roger |date=2015-10-07 |title='Courtesy Cards' Shield Bearer From Traffic Tickets |work=Metropolitan News-Enterprise |url=http://www.metnews.com/articles/2015/perspectives102715.htm |access-date=2023-06-05}}</ref> and Philadelphia.<ref name="steele">{{Cite news |last=Steele |first=Allison |date=2010-06-07 |title=Police say don't confuse courtesy cards with a free pass |language=en |work=Philadelphia Inquirer |url=https://www.inquirer.com/philly/news/local/20100607_Police_say_don_t_confuse_courtesy_cards_with_a_free_pass.html |access-date=2023-06-05}}</ref> 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.<ref name="grace"/> The cards were widespread in the United States in the 1950s, including by criminals. In 1976 the New Hampshire Governor handed them out to large contributors.<ref name="grace"/> The New York City Civilian Complaint Review Board in 2006 ruled the cards are private property and may not be confiscated without cause by police.<ref name="grace"/>

Law firms say that showing the card, and especially then asking for lenience, can be illegal if it is considered trying to influence an officer.<ref name="rosenblum">{{Cite web |date=2021-06-19 |title=Do PBA Cards Really Work? - Rosenblum Law |url=https://traffictickets.com/blog/pba-cards-work/ |access-date=2023-06-05 |website=traffictickets.com |language=en-US}}</ref><ref name="weiss">{{Cite web |last=Weiss |first=Matthew |date=2022-11-22 |title=What is a PBA Card and Will One Help Me Get Out of a Ticket? |url=https://nytrafficticket.com/what-is-a-pba-card-and-will-one-help-me-get-out-of-a-ticket/ |access-date=2023-06-05 |website=Weiss & Associates, P.C. |language=en-US}}</ref>

The cards have a racial effect, since police are disproportionately white. The cards go to whites disproportionately, including as Christmas gifts,<ref name="bal"/> leaving minorities with disproportionate tickets. The racial effect is increased when officers have quotas of tickets to issue, which then go disproportionately to minority citizens who lack a card.<ref name="helmore"/>

The cards have been used since at least 1936.<ref name="way"/><ref name="alex">{{Cite news |last=Alexander |first=Jack |date=1936-10-03 |title=Independent Cop, Profile of Police Commissioner Lewis J. Valentine |work=New Yorker |url=https://www.newyorker.com/magazine/1936/10/03/independent-cop-i}}</ref> 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.<ref name="bal">{{Cite news |last=Balsamini |first=Dean |date=2018-01-21 |title=Police union slashes number of 'get out of jail free' cards issued |language=en-US |work=New York Post |url=https://nypost.com/2018/01/21/police-union-slashes-number-of-get-out-of-jail-free-cards-issued/ |access-date=2023-06-05}}</ref><ref name="way"/>

===Legal basis for stops===
In the United States, traffic stops have been criticized for their use in police [[dragnet (policing)|dragnets]] to check compliance with laws such as those requiring the use of seat belts or those prohibiting driving while impaired. Some people have objected that the tactic violates the [[United States Constitution]]; the [[Fourth Amendment to the United States Constitution|Fourth Amendment to the Constitution]], part of the [[United States Bill of Rights|Bill of Rights]], contains a provision against [[Fourth Amendment to the United States Constitution|unreasonable search and seizure]]. However, the [[United States Supreme Court]] has ruled that a motor vehicle is subject to a diminished expectation of privacy as compared to a home.  Reasons include the fact that motor vehicles are typically driven on public streets, that said vehicles are generally subject to public licensing and registration requirements, and that said vehicles are generally held out to public view in a way different than that of traditional dwellings.

*In ''[[Delaware v. Prouse]]'', 440 U.S. 648 (1979), the U.S. Supreme Court ruled that the police stopping vehicles for no reason other than to check the drivers' licenses and registrations was unconstitutional.
*In ''[[New York v. Belton]]'', 453 U.S. 454 (1981), the U.S. Supreme Court ruled that when a police officer has made a lawful arrest of a driver, he may search the passenger area of the vehicle without obtaining a warrant. Recent Court decisions have limited the scope of the search even further.
*In ''[[Michigan Dept. of State Police v. Sitz]]'', 496 U.S. 444 (1990), the U.S. Supreme Court ruled that the use of [[sobriety checkpoint]]s is constitutional. Under the [[Ninth Amendment to the United States Constitution|Ninth Amendment to the U.S. Constitution]], states have the right to reasonably regulate the safety, health, and welfare of their citizens.
*In ''[[Illinois v. Caballes]]'', 543 U.S. 405 (2005), the U.S. Supreme Court held that a dog sniff, conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no individual has any right to possess, does not violate the Fourth Amendment.
*In ''[[Arizona v. Gant]]'', (2008), the U.S. Supreme Court ruled that an officer must demonstrate a threat to their safety or a need to preserve evidence related to the crime of arrest in order to search a vehicle pursuant to an arrest, distinguishing ''[[New York v. Belton]]''.
*In ''[[Rodriguez v. United States]]'' (2015), a case originating in federal court, the Supreme Court declared that the protraction of a traffic stop with the intent to use a [[sniffer dog]] to search for evidence for which no reasonable suspicion exists is violative of the [[Fourth Amendment to the United States Constitution|Fourth Amendment]].