Page 32 - TPA Journal November December2021

(2) Coinbase. In that regard, Gratkowski argues that transactions.” Unlike telephone call and bank
the district court erred in denying his suppression records, CSLI provides officers with “an all-
motion. We hold that it did not. encompassing record of the holder’s whereabouts”
and “provides an intimate window into a person’s
Applying the third-party doctrine, the Supreme life, revealing not only [an individual’s] particular
Court in U.S. v. Miller held that bank records were movements, but through them [their] familial,
not subject to Fourth Amendment protections. The political, professional, religious, and sexual
Court concluded that the bank records were “not associations.” Because individuals “compulsively
confidential communications but negotiable carry cell phones with them all the time[,]” cell
instruments,” which “contain[ed] only information phones have become “almost a feature of human
voluntarily conveyed to the banks and exposed to anatomy.” Thus, the Court held that CSLI
their employees in the ordinary course of business.” “implicate[d] privacy concerns far beyond those
It recognized that in enacting the Bank Secrecy Act, considered in Smith and Miller.”
Congress assumed that individuals lacked “any
legitimate expectation of privacy concerning the As for the voluntary exposure component, the
information kept in bank records.” Court noted that CSLI was not voluntarily shared
information for two reasons. First, “cell phones and
The Court has also held that the third-party doctrine the services they provide are such a pervasive and
applies to telephone call logs. It held that insistent part of daily life that carrying one is
individuals had no privacy interest in the telephone indispensable to participation in modern society.”
numbers they dialed because people generally do Second, CSLI does not require “any affirmative act
not have any actual expectation of such privacy and on the part of the user.” So long as the user has
“voluntarily convey[]” the dialed numbers to the their cell phone on, a third party receives CSLI.
phone company by placing a call.
Gratkowski cites Carpenter to support his
However, the Supreme Court recently concluded argument that he had a privacy interest in the
differently in the context of cell phones. Court held information held in the Bitcoin blockchain. But the
that individuals had a privacy interest in their cell information on Bitcoin’s blockchain is far more
phone location records, known as cell-site location analogous to the bank records in Miller and the
information (“CSLI”), despite the records being telephone call logs in Smith than the CSLI in
held by a third party. In discussing the third-party Carpenter.
doctrine, the Court noted that the sole act of sharing
did not eliminate an individual’s privacy interest. The nature of the information on the Bitcoin
Rather, the Court considered (1) “the nature of the blockchain and the voluntariness of the exposure
particular documents sought,” which includes weigh heavily against finding a privacy interest in
whether the sought information was limited and an individual’s information on the Bitcoin
meant to be confidential, and (2) the voluntariness blockchain. The Bitcoin blockchain records (1) the
of the exposure. amount of Bitcoin transferred, (2) the Bitcoin
address of the sending party, and (3) the Bitcoin
Regarding the nature of the information sought, the address of the receiving party. The information is
Court noted that “telephone call logs reveal little in limited. Moreover, transacting through Bitcoin is
the way of identifying information” and that checks not “a pervasive [or] insistent part of daily life,”
are “not confidential communications but and transferring and receiving Bitcoin requires an
negotiable instruments . . . used in commercial “affirmative act” by the Bitcoin address holder.

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