State Laws on Cell-Site Location Information
In the wake of the June 22nd landmark Supreme Court decision in Carpenter v. United States, it's a good time to review the laws of each state on cell-site location information. The American Civil Liberties Union has posted an interactive map here showing in the level of protection for CSLI in each of the 50 states.
No warrant is required in the red states.
The blue states require a warrant for real-time location tracking.
The green states require a warrant for CSLI.
Conflicting decisions have been issued in the purple states.

Note California and Colorado are among the states requiring a warrant for the location information, but whereas California requires a warrant for all cell phone location information, Colorado only requires a warrant for obtaining the information from devices, not from service providers.
In New Jersey a decision of the state supreme court ordered that a warrant was required for real time information, and in Illinois a state law was passed requiring a warrant for such information.
The Nevada Supreme Court ruled that no warrant is required for past CSLI.