Carpenter v. United States

Brief of Amici Curiae Electronic Frontier Foundation, Brennan Center for Justice, The Constitution Project, National Association of Criminal Defense Lawyers and National Association of Federal Defenders in Support of Petitioner.

Brief filed: 08/14/2017


Carpenter v. United States

United States Supreme Court; Case No. 16-402

Prior Decision

Decision below 819 F.3d 880 (6th Cir. Apr. 13, 2016).


There has been a dramatic increase in location data generated by cell phones, collected by third parties, and routinely obtained by law enforcement without a warrant. Cell Site Location Information (CSLI) paints a revealing portrait of a person's movements, presenting even greater privacy concerns than the GPS tracker at issue in Jones. The Third-Party Doctrine is "ill-suited to the digital age" and should not apply to CSLI. 

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Andrew Crocker, Jennifer Lynch, and Jamie Williams, Electronic Frontier Foundation, San Francisco, CA; David Oscar Markus, NACDL, Miami, FL.