Source: https://www.aclu.org/issues/privacy-technology/location-tracking/cell-phone-location-tracking-laws-state
Timestamp: 2019-04-19 22:16:58+00:00

Document:
Location records can reveal an enormous amount of information about a person, especially with the proliferation of smartphones that constantly track our whereabouts. Because privacy laws haven’t kept up with advances in technology, police have long claimed the authority to access this information from cell phone companies without warrants.
That’s changing. While Congress and the Supreme Court haven’t yet weighed in on whether a warrant should be required for location information, little by little, state legislatures and lower courts are expanding privacy protections for more and more Americans.
That does mean, however, that the status of your privacy protections depends on where you are. For example, your location information is protected in Montana, but not in Georgia. In Illinois, police need a warrant to know where you are right now, but not where you were last week. In California, your location information is protected against warrantless search by state and local police, but not by federal authorities. In other states, we’re still waiting for rulings, and in Florida, state and federal courts are at odds on the matter.
The map below details the status of cell phone location tracking laws by state. Click on any highlighted state for more information.
Eleventh Circuit Court of Appeals, United States v. Davis (2015): No warrant required for historical CSLI.
State law (2015) requires warrant for all cell phone location information. Does not constrain federal law enforcement.
State law (2014) requires warrant for location information from devices but not from service providers. Does not constrain federal law enforcement.
State law (2016) requires court order for all cell phone location information. Does not constrain federal law enforcement.
Third Circuit Court of Appeals, In re Application (2010): Magistrate judges have discretion to require warrant for historical CSLI, and third-party doctrine does not apply.
Florida Supreme Court, Tracey v. State (2014): Warrant required for real-time cell phone location tracking. May not constrain federal law enforcement.
State law (2014) requires warrant for real-time cell phone location information. Does not constrain federal law enforcement.
Sixth Circuit Court of Appeals, United States v. Carpenter: No warrant required for historical cell site location information.
Sixth Circuit Court of Appeals, United States v. Skinner (2012): No warrant required for short-term real-time cell phone location tracking.
Fifth Circuit Court of Appeals, In re Application (2013): No warrant required for historical CSLI.
State law (2013) requires warrant for all cell phone location information. Does not constrain federal law enforcement.
Fourth Circuit Court of Appeals, United States v. Graham (2016): No warrant required for historical CSLI.
Massachusetts Supreme Judicial Court, Commonwealth v. Augustine (2014): Warrant required for historical CSLI under state constitution. Does not constrain federal law enforcement.
State law (2014) requires warrant for all cell phone location information. Does not constrain federal law enforcement.
Nevada Supreme Court, Taylor v. State (2016): No warrant required for historical CSLI.
New Jersey Supreme Court, State v. Earls (2013): Warrant required for real-time cell phone location tracking under state constitution. Does not constrain federal law enforcement.
State law (2016) requires warrant for all cell phone location information. Does not constrain federal law enforcement.
State law (2014) requires warrant for real-time cell phone location information, but amended in 2015 to weaken protections. Does not constrain federal law enforcement.

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