Nabiha Syed provides a roundup of responses to the Supreme Court’s decision in United States v. Jones that warrantless attachment of a GPS tracking device constitutes a search under the Fourth Amendment. You can also find a selection of thoughts and commentaries on Concurring Opinions. Note that deciding that attaching a GPS to a car is a search under the Fourth Amendment is not the same as deciding that it always requires a warrant or that this particular search was unreasonable. But it’s still a pretty positive outcome for privacy advocates.
On first read of the decision, I find myself pleasantly surprised by Justice Scalia’s opinion, which seems to take a more expansive and protective approach than concurring opinions that focus on privacy but not trespass. I have yet to really sit down and digest it all, though.
Scott Greenfield provides his own take on the opinion and concurring opinions.