The Supreme Court will decide this term, in Chatrie v. U.S., whether executing a multi-step geofence warrant violated the Fourth Amendment. The en banc Fourth Circuit deadlocked 7-7 on what they took to be the relevant question: whether the gov't conducted a "search."
For years, courts have been confused about how to determine which government acts count as a "search" under the Amendment. More recently, the search tests that produce the confusion have been defended as historically rooted. They're not, and the historical evidence is overwhelming. A draft of my new article is up on SSRN:
papers.ssrn.com/sol3/papers.… Comments welcome at jwrench@ij.org.