By: Lilias Gordon,

You are walking out the door in a rush so you do a quick self pat-down search — phone, wallet, keys — good to go. Most of us take our phones everywhere. Phones keep our calendars, emails, photos, text messages, and just about everything else. We download applications that collect even more information. How much of that massive amount of information is private? Not much. First, there are multiple ways your phone can be tracked by both your service provider and the government. Second, there is a limited expectation of privacy over the content of a cell phone if a person is stopped by police officers. Third, we self-disclose massive amounts of information about ourselves over social media that can go to third parties or the government. So, when you pat down your pockets to make sure you don’t go anywhere without your phone, perhaps you are searching yourself so that nobody else has to.

Cell phones can be tracked by the government pulling information from your service provider. A person places or receives a call on their cell phone, which connects to the nearest cellular tower transmitting information through the strongest signal.[1] Service providers keep records about how long the call lasted, between whom, and most importantly the location of the call based on the tower that was being used.[2] This is how the government can get a hold of cell-site location information (CSLI) for both past calls and in real time.[3]

People generally do not have a reasonable expectation of privacy in the location data given from their cell phone GPS or by CSLI.[4] In fact, no search occurs when a person voluntarily uses their cell phone in public, that information goes to the service provider, then the government accesses that information, possibly to place a suspect at the scene of a crime.[5] This analysis is under the Katz test for reasonable expectation of privacy; Supreme Court has observed that there is never a physical intrusion because the GPS is just a part of the phone.[6]

This issue is being addressed by state legislatures — but much like T-Mobile, the coverage it is patchy.[7] Courts are divided on whether the Stored Communications Act makes it illegal for the government to track your location in real time without probable cause and a warrant.[8] Neither Congress nor the Supreme Court has settled the debate as to whether warrants should be required for the government to access location information through a person’s cell phone.[9] The majority of the South, minus Florida, has decided that no warrant is required to track a cell phone. Few states, California being one of them, require a warrant for all cell phone location information.[10] How the government can track a cell phone greatly depends on where a person is in the country.

Unfortunately, this is not the only way a person can be tracked using a cellphone. Cell site simulators (CSS) are a tool used by the FBI that act like a nearby cell phone tower, tricking a phone into sending all the data intended to be transmitted to the cell phone carrier.[11] This tool can be used by the government to find out a person’s cell phone number based on knowing only the person’s general location.[12] The opposite is also true; if an officer knows identifying information about a person’s phone, they can use a CSS to locate its exact location.[13] The government can use either a person’s general location or general identifying information about a phone to find out that phone’s exact location in real time using a CSS.

Additionally, the contents of a person’s phone may be subject to search. Consider, there is a reason most people have pass-codes protecting their phones. A typical smart phone can store anything from a detailed calendar, a person’s internet search history, pictures from a vacation, or every text message sent from that phone. The Supreme Court articulated in Riley that police may not search digital information on a cell phone seized from an individual who has been arrested legally unless they obtain a warrant. [14] But one of the major takeaways of this case was that the reasonable expectation of privacy does not extend to include all the data on an arrestee’s cell phone.[15]

The applications we install is at least one more way we use our phones to disclose a massive amount of information to private companies and potentially the government. For example, Snapchat has built a brand on pictures and videos that are self-deleting. Pitching Snapchat as secure is a thin vainer of privacy considering all the ways a picture sent over Snapchat can be recovered. First, a recipient can easily screenshot a picture, saving it to their phone.[16] Other companies have invented apps that automatically save Snapchat photos and videos to the recipient’s phone (without notifying the sender).[17] Sent Snapchats can also be dug out of a phone by forensics firms who work with law enforcement and lawyers.[18]

Snapchat’s Privacy Policy list all the information Snapchat collects from people who use their product and how this information is used.[19] Snapchat collects “whatever information you send through the service, such as Snaps and Chats to your friends,” “information about your location,” “images and other information from your device’s camera and photos,” “information that other users provide about you when they use [Snapchat] services.”[20] Snapchat’s Privacy Policy also answers the question of what they do with all the information they collect. For example, user’s information is shared with third-party targeting advertisers or in order to comply with any legal or governmental request.[21]

Cell phones are incredibly convenient and serve just about any purpose people can think of. It is no surprise we use them as much as we do. However, cell phones are also incredibly convenient for law enforcement.


[1] United States v. Jones, 908 F. Supp. 2d 203, 206 (D.D.C. 2012).

[2] Id. at 207.

[3] Id. at 210.

[4] United States v. Skinner, 690 F.3d 772, 777 (6th Cir. 2012).

[5] Id. at 779.

[6] Id. at 778.

[7] Cell Phone Location Tracking Laws By State, ACLU (accessed 10:43AM, Feb. 6, 2019).

[8] 1-2 Criminal Constitutional Law § 2.03 (2017).

[9] Id.

[10] Id.

[11] Coleman Torrans, How Did They Know That? Cell Site Simulators and the Secret Invasion of Privacy, 92 Tul. L. Rev. 519, 521 (2017).

[12] Id.

[13] Id.

[14] Riley v. California, 134 S. Ct. 2473, 2493 (2014).

[15] Id.

[16] Danielle Young, Now You See It, Now You Don’t… Or Do You?: Snapchat’s Deceptive Promotion of Vanishing Messages Violates Federal Trade Commission Regulations, 30 J. Marshall J. Info. Tech. & Privacy L. 827 (2014).

[17] Drew Guarini, ‘Snap Save,’ New iPhoneApp, Lets You Save Snapchats–Without Letting The Sender Know, Huff. Post (Aug. 9, 2013),

[18] DL Clade, Forensics Firm Discovers that Snapchat Photos Don’t Disappear After All, PETA PIXEL (May 10, 2013),

[19] Privacy Policy, Snapchat, (last visited Feb. 6, 2018).

[20] Id.

[21] Id.

Image Source: