With the advent of wireless technology, there have been growing concerns about the protection of individual privacy against arbitrary intrusion by government agents. While cell phones help us stay in touch with the important people in our lives, the technology also has the inherent potential for exposing our private lives to others. Over the last couple of decades, the Courts have continued to evolve the Fourth Amendment doctrine to keep up with the privacy concerns raised by the technological advancement in cell phones.

The Fourth Amendment to the United States Constitution guards against unreasonable searches and seizures as follows:

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

U.S. Const., amend. IV.

In US v. Katz, 389 U.S. 347, 367 (1967), the U.S. Supreme Court set forth a two-part test to determine whether search was conducted that implicated the Fourth Amendment. Under the two-part test the Courts need to determine:

  1. Whether the individual has exhibited an actual expectation of privacy; and
  2. Whether the society is prepared to recognize that this expectation of privacy is (objectively) reasonable.  

That case was considered a landmark because it made government wiretapping subject to the Fourth Amendment’s warrant requirements.

In 1979, the U.S. Supreme Court also determined that individuals had no reasonable expectation of privacy in the phone numbers used to make or receive calls on their phone.  In that case, Smith v. Maryland, 442 U.S. 735 (1979), the Supreme Court determined that “the installation and use of [a telephone number] pen register was not a “search” within the meaning of the Fourth Amendment, and hence no warrant was required. Pp. 739-746.”  The Court carved out a third party exception to the Fourth Amendment analysis as follows:

Petitioner in all probability entertained no actual expectation of privacy in the phone numbers he dialed, and even if he did, his expectation was not “legitimate.” First, it is doubtful that telephone users in general have any expectation of privacy regarding the numbers they dial, since they typically know that they must convey phone numbers to the telephone company and that the company has facilities for recording this information and does in fact record it for various legitimate business purposes. And petitioner did not demonstrate an expectation of privacy merely by using his home phone rather than some other phone, since his conduct, although perhaps calculated to keep the contents of his conversation private, was not calculated to preserve the privacy of the number he dialed. Second, even if petitioner did harbor some subjective expectation of privacy, this expectation was not one that society is prepared to recognize as “reasonable.” When petitioner voluntarily conveyed numerical information to the phone company and “exposed” that information to its equipment in the normal course of business, he assumed the risk that the company would reveal the information [442 U.S. 735, 736] to the police, cf. United States v. Miller, 425 U.S. 735 .

Id. at 741-746.

It is extremely important to contrast the difference between the data conveyed on the pen register in Smith v. Maryland  and cellular telephone data that is automatically sent to the cell phone carrier even without the subscriber dialing any numbers. The data that is automatically sent to the cell phone carrier also contains the “cell site location information” (CSLI). The historical CSLI identifies the cell tower to which the customer was connected at the beginning of the call and at the end of the call. Thus, the historical CSLI data can be used to track the previous movements of the cell phone user. Similarly, prospective CSLI data can be used to track the movements of the cell phone user in future.

Several federal courts have held that cell phone users have a reasonable expectation of privacy in the cell site location records. Therefore, government cannot access CSLI without a warrant as per the Fourth Amendment. But the majority of federal courts have held that this reasonable expectation of privacy is for the prospective CSLI only.  However, recently, the United States District Court for the Eastern District of New York held that the exception to third party disclosure should also apply to historical CSLI because cell phone users have a reasonable expectation of privacy in the cumulative cell site location records.

As the Fourth Amendment doctrine and the scope of individual’s expectation of privacy continue to evolve with technological developments, attorneys will continue to challenge the legality of government’s access to these technological advances.

Comments/Questions: gdn@gdnlaw.com

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