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Police Technology Case Law Index

Research leading cases involving Fourth Amendment doctrine, electronic surveillance, location tracking, cell phones, digital records, pole cameras, aerial observation, vehicle searches, bodily evidence, curtilage, geofence warrants, DNA and biometrics, special-needs searches, and technology-assisted police investigations.

63Published Case Analyses
12Research Topics
1967–2026Decisions Represented

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New to Fourth Amendment technology law? These six decisions provide a strong foundation for understanding privacy, digital evidence, location tracking, home protection, and modern police technology.

Foundational PrivacyKatz v. United StatesReasonable expectations of privacy and the move beyond property-based Fourth Amendment analysis. Location TrackingUnited States v. JonesGPS tracking, physical trespass, and long-term surveillance. Digital DevicesRiley v. CaliforniaWhy searching a smartphone differs from searching ordinary physical objects. Digital Location DataCarpenter v. United StatesHistorical cell-site information and limits on the third-party doctrine. Geofence WarrantsChatrie v. United States (2026)Geofence warrants and constitutional limits on digital dragnet techniques. Home ProtectionCaniglia v. StromWhy generalized community caretaking does not create a freestanding home-entry exception.
Browse A–ZBrowse by TopicView TimelineTechnology CrosswalkFourth Amendment Timeline

Browse A–Z

ABCDFHIKLMOPRSUVW

A

Arizona v. Gant 2009 · U.S. Supreme Court Arizona v. Hicks 1987 · U.S. Supreme Court

B

Berger v. New York 1967 · U.S. Supreme Court Birchfield v. North Dakota 2016 · U.S. Supreme Court Brigham City v. Stuart 2006 · U.S. Supreme Court

C

California v. Acevedo 1991 · U.S. Supreme Court California v. Ciraolo 1986 · U.S. Supreme Court California v. Greenwood 1988 · U.S. Supreme Court Caniglia v. Strom 2021 · U.S. Supreme Court Carpenter v. United States 2018 · U.S. Supreme Court Chatrie v. United States (2026) 2026 · U.S. Supreme Court Commonwealth v. Comenzo 2022 · Massachusetts Supreme Judicial Court Commonwealth v. Mora 2020 · Massachusetts Supreme Judicial Court

D

District of Columbia v. Wesby 2018 · U.S. Supreme Court Dow Chemical Co. v. United States 1986 · U.S. Supreme Court

F

Florida v. Harris 2013 · U.S. Supreme Court Florida v. Jardines 2013 · U.S. Supreme Court Florida v. Riley 1989 · U.S. Supreme Court

H

Horton v. California 1990 · U.S. Supreme Court

I

Illinois v. Caballes 2005 · U.S. Supreme Court Illinois v. Gates 1983 · U.S. Supreme Court Illinois v. Wardlow 2000 · U.S. Supreme Court

K

Kansas v. Glover 2020 · U.S. Supreme Court Katz v. United States 1967 · U.S. Supreme Court Kyllo v. United States 2001 · U.S. Supreme Court

L

Lange v. California 2021 · U.S. Supreme Court Leaders of a Beautiful Struggle v. Baltimore Police Department 2021 · U.S. Court of Appeals, Fourth Circuit

M

Maryland v. King 2013 · U.S. Supreme Court Maryland v. Pringle 2003 · U.S. Supreme Court Minnesota v. Dickerson 1993 · U.S. Supreme Court Missouri v. McNeely 2013 · U.S. Supreme Court

O

Oliver v. United States 1984 · U.S. Supreme Court

P

People v. Tafoya 2021 · Colorado Supreme Court Prado Navarette v. California 2014 · U.S. Supreme Court

R

Riley v. California 2014 · U.S. Supreme Court Rodriguez v. United States 2015 · U.S. Supreme Court

S

Skinner v. Railway Labor Executives' Association 1989 · U.S. Supreme Court Smith v. Maryland 1979 · U.S. Supreme Court

U

United States v. Ackerman 2016 · U.S. Court of Appeals, Tenth Circuit United States v. Arvizu 2002 · U.S. Supreme Court United States v. Cuevas-Sanchez 1987 · U.S. Court of Appeals, Fifth Circuit United States v. Davis 2015 · U.S. Court of Appeals, Eleventh Circuit United States v. Dunn 1987 · U.S. Supreme Court United States v. Forrester 2007 · U.S. Court of Appeals, Ninth Circuit United States v. Graham 2016 · U.S. Court of Appeals, Fourth Circuit United States v. Hay 2024 · U.S. Court of Appeals, Tenth Circuit United States v. Houston 2016 · U.S. Court of Appeals, Sixth Circuit United States v. Jacobsen 1984 · U.S. Supreme Court United States v. Jones 2012 · U.S. Supreme Court United States v. Karo 1984 · U.S. Supreme Court United States v. Kendrick 2026 · U.S. Court of Appeals, Seventh Circuit United States v. Knotts 1983 · U.S. Supreme Court United States v. Miller 1976 · U.S. Supreme Court United States v. Moore-Bush 2022 · U.S. Court of Appeals, First Circuit United States v. Place 1983 · U.S. Supreme Court United States v. Ross 1982 · U.S. Supreme Court United States v. Tuggle 2021 · U.S. Court of Appeals, Seventh Circuit United States v. U.S. District Court 1972 · U.S. Supreme Court United States v. Warshak 2010 · U.S. Court of Appeals, Sixth Circuit United States v. White 1971 · U.S. Supreme Court United States v. Wurie 2013 · First Circuit; affirmed with Riley in 2014

V

Van Buren v. United States 2021 · U.S. Supreme Court

W

Whren v. United States 1996 · U.S. Supreme Court

Browse by Topic

Digital Privacy & Records

United States v. Miller 1976 · U.S. Supreme Court United States v. Wurie 2013 · First Circuit; affirmed with Riley in 2014 Carpenter v. United States 2018 · U.S. Supreme Court Chatrie v. United States (2026) 2026 · U.S. Supreme Court Riley v. California 2014 · U.S. Supreme Court Smith v. Maryland 1979 · U.S. Supreme Court United States v. Ackerman 2016 · U.S. Court of Appeals, Tenth Circuit United States v. Davis 2015 · U.S. Court of Appeals, Eleventh Circuit United States v. Forrester 2007 · U.S. Court of Appeals, Ninth Circuit United States v. Graham 2016 · U.S. Court of Appeals, Fourth Circuit United States v. Warshak 2010 · U.S. Court of Appeals, Sixth Circuit United States v. White 1971 · U.S. Supreme Court Van Buren v. United States 2021 · U.S. Supreme Court

Location Tracking & Mosaic Theory

Carpenter v. United States 2018 · U.S. Supreme Court Chatrie v. United States (2026) 2026 · U.S. Supreme Court Leaders of a Beautiful Struggle v. Baltimore Police Department 2021 · U.S. Court of Appeals, Fourth Circuit People v. Tafoya 2021 · Colorado Supreme Court United States v. Davis 2015 · U.S. Court of Appeals, Eleventh Circuit United States v. Graham 2016 · U.S. Court of Appeals, Fourth Circuit United States v. Hay 2024 · U.S. Court of Appeals, Tenth Circuit United States v. Jones 2012 · U.S. Supreme Court United States v. Karo 1984 · U.S. Supreme Court United States v. Knotts 1983 · U.S. Supreme Court United States v. Moore-Bush 2022 · U.S. Court of Appeals, First Circuit United States v. Tuggle 2021 · U.S. Court of Appeals, Seventh Circuit

Pole Cameras & Persistent Surveillance

Commonwealth v. Comenzo 2022 · Massachusetts Supreme Judicial Court Commonwealth v. Mora 2020 · Massachusetts Supreme Judicial Court People v. Tafoya 2021 · Colorado Supreme Court United States v. Cuevas-Sanchez 1987 · U.S. Court of Appeals, Fifth Circuit United States v. Hay 2024 · U.S. Court of Appeals, Tenth Circuit United States v. Houston 2016 · U.S. Court of Appeals, Sixth Circuit United States v. Kendrick 2026 · U.S. Court of Appeals, Seventh Circuit United States v. Moore-Bush 2022 · U.S. Court of Appeals, First Circuit United States v. Tuggle 2021 · U.S. Court of Appeals, Seventh Circuit

Home, Curtilage & Open Fields

Brigham City v. Stuart 2006 · U.S. Supreme Court Arizona v. Hicks 1987 · U.S. Supreme Court California v. Ciraolo 1986 · U.S. Supreme Court Caniglia v. Strom 2021 · U.S. Supreme Court Commonwealth v. Comenzo 2022 · Massachusetts Supreme Judicial Court Commonwealth v. Mora 2020 · Massachusetts Supreme Judicial Court Florida v. Jardines 2013 · U.S. Supreme Court Florida v. Riley 1989 · U.S. Supreme Court Kyllo v. United States 2001 · U.S. Supreme Court Lange v. California 2021 · U.S. Supreme Court Oliver v. United States 1984 · U.S. Supreme Court People v. Tafoya 2021 · Colorado Supreme Court United States v. Cuevas-Sanchez 1987 · U.S. Court of Appeals, Fifth Circuit United States v. Dunn 1987 · U.S. Supreme Court United States v. Hay 2024 · U.S. Court of Appeals, Tenth Circuit United States v. Houston 2016 · U.S. Court of Appeals, Sixth Circuit United States v. Karo 1984 · U.S. Supreme Court United States v. Moore-Bush 2022 · U.S. Court of Appeals, First Circuit United States v. Tuggle 2021 · U.S. Court of Appeals, Seventh Circuit

Aerial & Technology Surveillance

California v. Ciraolo 1986 · U.S. Supreme Court Dow Chemical Co. v. United States 1986 · U.S. Supreme Court Florida v. Riley 1989 · U.S. Supreme Court Kyllo v. United States 2001 · U.S. Supreme Court Leaders of a Beautiful Struggle v. Baltimore Police Department 2021 · U.S. Court of Appeals, Fourth Circuit United States v. Karo 1984 · U.S. Supreme Court United States v. Knotts 1983 · U.S. Supreme Court

Electronic Surveillance

Berger v. New York 1967 · U.S. Supreme Court Katz v. United States 1967 · U.S. Supreme Court Smith v. Maryland 1979 · U.S. Supreme Court United States v. Forrester 2007 · U.S. Court of Appeals, Ninth Circuit United States v. U.S. District Court 1972 · U.S. Supreme Court United States v. White 1971 · U.S. Supreme Court

Traffic Stops & Reasonable Suspicion

District of Columbia v. Wesby 2018 · U.S. Supreme Court Illinois v. Caballes 2005 · U.S. Supreme Court Illinois v. Wardlow 2000 · U.S. Supreme Court Kansas v. Glover 2020 · U.S. Supreme Court Minnesota v. Dickerson 1993 · U.S. Supreme Court Prado Navarette v. California 2014 · U.S. Supreme Court Rodriguez v. United States 2015 · U.S. Supreme Court United States v. Arvizu 2002 · U.S. Supreme Court United States v. Place 1983 · U.S. Supreme Court Whren v. United States 1996 · U.S. Supreme Court

Probable Cause & Warrants

Berger v. New York 1967 · U.S. Supreme Court California v. Acevedo 1991 · U.S. Supreme Court District of Columbia v. Wesby 2018 · U.S. Supreme Court Florida v. Harris 2013 · U.S. Supreme Court Horton v. California 1990 · U.S. Supreme Court Illinois v. Gates 1983 · U.S. Supreme Court Maryland v. Pringle 2003 · U.S. Supreme Court Missouri v. McNeely 2013 · U.S. Supreme Court United States v. Ross 1982 · U.S. Supreme Court United States v. U.S. District Court 1972 · U.S. Supreme Court United States v. Warshak 2010 · U.S. Court of Appeals, Sixth Circuit Whren v. United States 1996 · U.S. Supreme Court

Vehicle Searches

Arizona v. Gant 2009 · U.S. Supreme Court California v. Acevedo 1991 · U.S. Supreme Court Maryland v. Pringle 2003 · U.S. Supreme Court United States v. Ross 1982 · U.S. Supreme Court

Canine Searches

Florida v. Harris 2013 · U.S. Supreme Court Florida v. Jardines 2013 · U.S. Supreme Court Illinois v. Caballes 2005 · U.S. Supreme Court Rodriguez v. United States 2015 · U.S. Supreme Court United States v. Place 1983 · U.S. Supreme Court

Bodily Evidence, DNA & Biometrics

Birchfield v. North Dakota 2016 · U.S. Supreme Court Maryland v. King 2013 · U.S. Supreme Court Missouri v. McNeely 2013 · U.S. Supreme Court Skinner v. Railway Labor Executives' Association 1989 · U.S. Supreme Court

Search Exceptions & Evidence Doctrines

Brigham City v. Stuart 2006 · U.S. Supreme Court United States v. Miller 1976 · U.S. Supreme Court United States v. Wurie 2013 · First Circuit; affirmed with Riley in 2014 Arizona v. Gant 2009 · U.S. Supreme Court Arizona v. Hicks 1987 · U.S. Supreme Court Birchfield v. North Dakota 2016 · U.S. Supreme Court California v. Greenwood 1988 · U.S. Supreme Court Caniglia v. Strom 2021 · U.S. Supreme Court Dow Chemical Co. v. United States 1986 · U.S. Supreme Court Horton v. California 1990 · U.S. Supreme Court Katz v. United States 1967 · U.S. Supreme Court Lange v. California 2021 · U.S. Supreme Court Maryland v. King 2013 · U.S. Supreme Court Minnesota v. Dickerson 1993 · U.S. Supreme Court Missouri v. McNeely 2013 · U.S. Supreme Court Riley v. California 2014 · U.S. Supreme Court United States v. Ackerman 2016 · U.S. Court of Appeals, Tenth Circuit United States v. Jacobsen 1984 · U.S. Supreme Court United States v. Kendrick 2026 · U.S. Court of Appeals, Seventh Circuit

Case Timeline

2026
Chatrie v. United States (2026)
U.S. Supreme Court United States v. Kendrick
U.S. Court of Appeals, Seventh Circuit
2024
United States v. Hay
U.S. Court of Appeals, Tenth Circuit
2022
Commonwealth v. Comenzo
Massachusetts Supreme Judicial Court United States v. Moore-Bush
U.S. Court of Appeals, First Circuit
2021
Caniglia v. Strom
U.S. Supreme Court Lange v. California
U.S. Supreme Court Leaders of a Beautiful Struggle v. Baltimore Police Department
U.S. Court of Appeals, Fourth Circuit People v. Tafoya
Colorado Supreme Court United States v. Tuggle
U.S. Court of Appeals, Seventh Circuit Van Buren v. United States
U.S. Supreme Court
2020
Commonwealth v. Mora
Massachusetts Supreme Judicial Court Kansas v. Glover
U.S. Supreme Court
2018
Carpenter v. United States
U.S. Supreme Court District of Columbia v. Wesby
U.S. Supreme Court
2016
Birchfield v. North Dakota
U.S. Supreme Court United States v. Ackerman
U.S. Court of Appeals, Tenth Circuit United States v. Graham
U.S. Court of Appeals, Fourth Circuit United States v. Houston
U.S. Court of Appeals, Sixth Circuit
2015
Rodriguez v. United States
U.S. Supreme Court United States v. Davis
U.S. Court of Appeals, Eleventh Circuit
2014
Prado Navarette v. California
U.S. Supreme Court Riley v. California
U.S. Supreme Court United States v. Wurie
Companion case resolved with Riley · U.S. Supreme Court
2013
Florida v. Harris
U.S. Supreme Court Florida v. Jardines
U.S. Supreme Court Maryland v. King
U.S. Supreme Court Missouri v. McNeely
U.S. Supreme Court United States v. Wurie
U.S. Court of Appeals, First Circuit
2012
United States v. Jones
U.S. Supreme Court
2010
United States v. Warshak
U.S. Court of Appeals, Sixth Circuit
2009
Arizona v. Gant
U.S. Supreme Court
2007
United States v. Forrester
U.S. Court of Appeals, Ninth Circuit
2006
Brigham City v. Stuart
U.S. Supreme Court
2005
Illinois v. Caballes
U.S. Supreme Court
2003
Maryland v. Pringle
U.S. Supreme Court
2002
United States v. Arvizu
U.S. Supreme Court
2001
Kyllo v. United States
U.S. Supreme Court
2000
Illinois v. Wardlow
U.S. Supreme Court
1996
Whren v. United States
U.S. Supreme Court
1993
Minnesota v. Dickerson
U.S. Supreme Court
1991
California v. Acevedo
U.S. Supreme Court
1990
Horton v. California
U.S. Supreme Court
1989
Florida v. Riley
U.S. Supreme Court Skinner v. Railway Labor Executives' Association
U.S. Supreme Court
1988
California v. Greenwood
U.S. Supreme Court
1987
Arizona v. Hicks
U.S. Supreme Court United States v. Cuevas-Sanchez
U.S. Court of Appeals, Fifth Circuit United States v. Dunn
U.S. Supreme Court
1986
California v. Ciraolo
U.S. Supreme Court Dow Chemical Co. v. United States
U.S. Supreme Court
1984
Oliver v. United States
U.S. Supreme Court United States v. Jacobsen
U.S. Supreme Court United States v. Karo
U.S. Supreme Court
1983
Illinois v. Gates
U.S. Supreme Court United States v. Knotts
U.S. Supreme Court United States v. Place
U.S. Supreme Court
1982
United States v. Ross
U.S. Supreme Court
1979
Smith v. Maryland
U.S. Supreme Court
1976
United States v. Miller
U.S. Supreme Court
1972
United States v. U.S. District Court
U.S. Supreme Court
1971
United States v. White
U.S. Supreme Court
1967
Berger v. New York
U.S. Supreme Court Katz v. United States
U.S. Supreme Court
Library status: 63 published case analyses · 12 research topics · reviewed August 16, 2026. Use the Technology Crosswalk to connect cases to specific police technologies, and the Fourth Amendment Timeline for chronological context.