US supreme court rules geofence warrants require constitutional privacy protections

Law enforcement's use of warrants sweeping smartphone location data requires privacy protections, court rules

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The US supreme court has ruled that law enforcement's use of sprawling warrants that sweep up smartphone location data requires privacy protections under the fourth amendment, in a boost to critics who view their use as an unconstitutional dragnet.

Justice Elena Kagan wrote the majority opinion, which held that the sensitive data scooped up by geofence warrants" counts as a fourth amendment search, and offers individuals a reasonable expectation of privacy", even if they may be in a public area.