Whatever the status of the third-party doctrine after Carpenter, nothing would change as to subpoenaing IP address information in a child pornography case. “The information at issue here falls comfortably within the scope of the third-party doctrine.” United States v. Contreras, 2018 U.S. App. LEXIS 27795 (5th Cir. Oct. 1, 2018):
I. Contreras had no reasonable expectation of privacy in Frontier’s records
We first address whether Contreras had a reasonable expectation of privacy in the family address as contained in Frontier’s records. In a series of precedents dating back to 1976, the Supreme Court has found that “a person has no legitimate expectation of privacy in information … voluntarily turn[ed] over to third parties,” “even if the information is revealed on the assumption that it will be used only for a limited purpose.” Carpenter v. United States, 138 S. Ct. 2206, 2216, 201 L. Ed. 2d 507 (2018) (quoting Smith v. Maryland, 442 U.S. 735, 743-44, 99 S. Ct. 2577, 61 L. Ed. 2d 220 (1979) and United States v. Miller, 425 U.S. 435, 443, 96 S. Ct. 1619, 48 L. Ed. 2d 71 (1976)). The third-party doctrine has limits: in Carpenter, the Supreme Court declined to extend the rule to cell-site records that convey “a detailed and comprehensive record of [a] person’s movements.” Id. at 2217. But the third-party doctrine continues to apply to “business records that might incidentally reveal location information,” including telephone numbers and bank records. Id. at 2220.
The information at issue here falls comfortably within the scope of the third-party doctrine. Frontier’s records revealed only that the IP address was associated with the Contreras’s Brownwood residence. They had no bearing on any person’s day-to-day movement. Contreras lacked a reasonable expectation of privacy in that information.