There is no reasonable expectation of privacy in a license plate, and the Fourth Amendment doesn’t prohibit running the tags for any reason. State v. Abrams, 2018 Ala. Crim. App. LEXIS 24 (Apr. 27, 2018).
The government obtained internet routing information from Google and Comcast, and that’s precisely the information obtainable without a search warrant under Miller. See United Statesv. Ulbricht, 858 F.3d 71 , 96 (2d Cir. 2017). United States v. Hammalian, 2018 U.S. Dist. LEXIS 69621 (D. Vt. Apr. 25, 2018).*