Hands-Off My License Plate: The Case for Applying 4th Amendment Protections to License Plate Numbers.
Theophilus O. Agbi
The Fourth Amendment protects an individual’s right to privacy. However, applying these protections in the public sphere is a tricky endeavor. For starters, one must balance individual privacy rights with public safety. This means factoring in law enforcement’s need to access private information in order to protect the public. Overlaying this calculation is modern technology, which allows people to quickly store and access massive amounts of data in previously unimaginable ways.
License plate numbers sit at the confluence of these issues. These funny little strings of letters and numbers refer to a file that is populated with both private information collected from the Department of Motor Vehicles (DMV) and public information. While this information is always present in the public sphere, it is invisible to most. Only a special few, like law enforcement, have the technology and authority to access these files. What is most ingenious about this system is it allows private information to further public safety while hiding in plain sight, thus striking a perfect balance between individual privacy and public welfare––at least in theory.
In practice, officers can, and do, access a driver’s private information without any apparent cause or justification. Courts sanction this practice by ruling that the Fourth Amendment does not apply to a driver’s license plate number. With this blessing from the courts, certain states are taking the practice one step further and they are installing automatic license plate readers (ALPRs). These electronic devices systematically catalogue license plate numbers, thus allowing the State to surveil its population. This perpetual surveillance of citizens, all stems from the state’s unfettered right to access the information on license plates. To have any hope of combatting ALPRs, one must first establish that the Fourth Amendment protects license plate numbers.
This note will argue that the Fourth Amendment extends to license plates and, therefore, that law enforcement officers cannot search a driver’s license plate number without cause. Part II of this note lays a brief history of the Amendment in order to highlight some of its key purposes, often excluded from the discussion. Part III outlines the main arguments that federal courts have advanced to deny Fourth Amendment protections for license plates. Part IV rebuts these arguments and advances alternate ways of tackling this issue. Finally, Part V concludes with a brief discussion on how the proposals in this note apply to the broader fight over ALPRs.
 See Cardwell v. Lewis, 417 U.S. 583, 589 (1974) (“The decisions of this Court (the Supreme Court) have time and again underscored the essential purpose of the Fourth Amendment [is] to shield the citizen from unwarranted intrusions into his privacy.”).
 See Terry v. Ohio, 392 U.S. 1, 22–26 (1968) (balancing individual privacy rights against governmental interest in public safety).
 See Stephen Dycus et al., National Security Law 562–63 (Vicki Been et al. eds., 5th ed. 2011) (citing United States v. U.S. Dist. Court for the E. Dist. of Mich. S. Div., 407 U.S. 297, 314–17 (1972)) (balancing the government’s interest in domestic security and individual’s right to be from unreasonable electronic surveillance); How Information is Protected or Disclosed, dmv.ca.gov, (last visited Oct. 18 2019) https://www.dmv.ca.gov/portal/dmv/detail/dl/how_info_shared (detailing laws that govern release of private DMV information to law enforcement).
 See Joel R. Reidenberg, Privacy in Public, 69 U. Miami L. Rev. 141, 145–46 (2014) (articulating how cellphones, drones, and big data projects are complicating privacy).
 How Information is Protected or Disclosed, dmv.ca.gov, (last visited Oct. 18 2019) https://www.dmv.ca.gov/portal/dmv/detail/dl/how_info_shared (detailing laws that govern release of private DMV information to law enforcement).
 Prohibition on Release and Use of Certain Personal Information from State Motor Vehicle Records, 18 U.S.C §2721 (2000); Emily Delbridge, Can I Run a License Plate Number for Free?, TheBalance.com, (last visited Oct. 18, 2019) https://www.thebalance.com/can-i-run-a-license-plate-number-for-free-3861067.
 See, e.g., Olabisiomotosho v. City of Houston, 185 F.3d 521, 529 (5th Cir. 1999) (allowing officers to search a driver’s license plate without cause because the Fourth Amendment does not protect license plates); United States v. Ellison, 462 F.3d 557, 563 (6th Cir. 2006) (holding that a LIEN system search of a license plate did not violate the Fourth Amendment, since license plates are not protected by the Amendment).
 Olabisiomotosho, 185 F.3d at 529; Ellison, 462 F.3d at 563.
 National Conference of State Legislatures, Automated License Plate Readers: State Statutes, ncsl.org, (Mar. 15, 2019) http://www.ncsl.org/research/telecommunications-and-information-technology/state-statutes-regulating-the-use-of-automated-license-plate-readers-alpr-or-alpr-data.aspx.
 Electronic Frontiers Foundation, Automated License Plate Readers (ALPRs), eff.org, (Last visited Oct. 18, 2019). https://www.eff.org/pages/automated-license-plate-readers-alpr.