Thread by @OrinKerr

In dicta, magistrate judge concludes that govt use of a cell site simulator is a search requiring a warrant because it might be used to locate a phone in a place where there's an REP. (DDC, 3/25/21) (Faruqui, M.J)

Quick thread.

drive.google.com/file/d/1KLyaNf… #N

First, why it's dicta: The issue arose when the government applied for a warrant, so no one was trying to conduct surveillance without a warrant. (Also, I don't tend to think Article III allows a merits ruling like this now, as how the 4A applies is not yet a ripe dispute.)

On the merits, the court's conclusion that a search occurs if a search might occur -- if a tool might be used to conduct a search -- seems wrong in light of United States v. Karo, which limited but did not overturn Knotts. scholar.google.com/scholar_case?c…

I recognize the passage from Kyllo that the judge relies on, reprinted below. But I don't see it as upsetting the coexistence of Knotts (no search if device doesn't reveal info inside home) and Karo (search requiring warrant if it does reveal info inside home).

As a practical matter this won't make much of a difference, though. As Karo noted, if the govt is going to need a warrant if the device might reveal info from in a home, they'll get a warrant anyway just in case because they won't know in advance.

Note that this result matches the result of the 1st 4A ruling on cell-site simulators, Andrews from 2016, but on a somewhat different rationale.
washingtonpost.com/news/volokh-co…

Part of what makes this different rationale interesting is Footnote 4 of the opinion, in which Judge Faruqui suggests that a magistrate judge's signing a warrant application is an implicit ruling that a warrant is indeed required.

Respectfully, I don't think that's right. Rule 41 is mandatory, not permissive: A magistrate judge has no power to deny a warrant application on the ground no warrant is needed. Cf. NY Telephone, ruling a Rule 41 warrant can be used for a pen register. scholar.google.com/scholar_case?c…

There's lots of other really interesting stuff in the opinion for fellow surveillance law nerds, including that cell-site simulators are not tracking warrants and about the permitted period of delayed notice (holding that the 365 day delay requested was too long). V. interesting.