Parking Enforcement, Chalk, License Plates Readers and the Fourth Amendment

Author: Attorney Marcus J. Berghahn
Phone: 608-257-0945

Given that parking tickets are probably one of the most common and annoying types of police contacts that a citizen may have, it’s not surprising that a smart attorney found the right case to challenge the manner in which parking restrictions were enforced:  by chalking tires.  In Madison, a number of parking enforcement vehicles employ tire chalking and a virtual counterpart: automated license plate reading technology.

Within the last year two different courts addressed these technologies in legal challenges to the question of whether the technology violated the Fourth Amendment’s proscription against unreasonable searches and seizures.  Chalking tires was found by one court to violate the Fourth Amendment, but the use of automated license plate readers (on the facts of the case) did not violate the Fourth Amendment.  Both cases highlight interesting issues relating to the Fourth Amendment—and parking tickets, an uncommon pairing.

The City of Saginaw, Michigan, uses a common parking enforcement practice known as “chalking:” parking enforcement officers uses chalk to mark the tires of parked vehicles to track how long they have been parked.  Parking enforcement officers return to the car after the posted time for parking has passed, and if the chalk marks are still there—a sign that the vehicle has not moved—the officer issues a citation.  A resident and frequent recipient of parking tickets, sued the City alleging that chalking violated her rights under the Fourth Amendment.  The City moved to dismiss the action, and the federal district court granted the City’s motion, finding that, while chalking may be a search under the Fourth Amendment, the search was reasonable.  

The Sixth Circuit Court of Appeals reversed the District Court’s decision, and remanded the case.  Taylor v. City of Saginaw, 922 F.3d 328 (6th Cir. 2019).  The Court of Appeals held that the chalking was a search, and that the City failed to demonstrate that an exception to the reasonableness requirement applied. 

Chalking was found to be a search under United States v. Jones, 565 U.S. 400 (2012)Jones holds that when governmental invasions are accompanied by physical intrusions, a search occurs when the government: (1) trespasses upon a constitutionally protected area, (2) to obtain information.  Id. at 404-405.  As the district court aptly noted, “[d]espite the low-tech nature of the investigative technique …, the chalk marks clearly provided information [to the parking enforcement officer].”  This amounts to an attempt to obtain information under Jones. 

The City, however, failed to meet its burden in establishing an exception to the warrant requirement.  The Court held that neither the community caretaking exception nor the motor-vehicle exception applied on the facts.

But would the use of virtual chalking through the use of automated license plate readers end differently?  Potentially. 

The use of automated license plate readers was examined by the Massachusetts Supreme Judicial Court in Commonwealth v. McCarthy, 484 Mass. 493 (2020), a case that involved a police investigation into suspected of drug distribution.  Police used automatic license plate readers on two bridges to track a suspect’s movements, and arrest him. 

Automatic license plate readers are cameras combined with software that allows them to identify and “read” license plates on passing vehicles.  When such a device identifies a license plate, it records a photograph of the plate, the system’s interpretation of the license plate number, and other data, such as the date, time, location, direction of travel, and travel lane.  The readers produce two related types of information: real-time alerts and historical data.  First, police can enter license plate numbers onto a “hot list,” and choose users to be notified about any new “hits” for that plate number.  If a camera in the reader system detects a license plate that matches a number on the hot list, the system sends an electronic mail message or text.  The alert sends an image of the plate, along with the date, time, location, and direction of travel.  Second, police can search by license plate number for any historical matches stored in the database.

In McCarthy, police used historical data derived from these devices to reveal the number of times he crossed the bridges over a three-month period.  The police were also alerted in real-time when he crossed the bridges and used this information to arrest him.  The case thus presented the question of whether the readers produced a detailed enough picture of an individual’s movements so as to infringe upon a reasonable expectation that the government will not electronically monitor that person’s comings and goings in public over a sustained period of time.  The technology could result in such monitoring that a mosaic picture of an individual’s comings and goings could be created by police such that the monitoring would be unreasonable under the Fourth Amendment.  The Court found that with enough cameras in enough locations, the historic location data from such a system would invade a reasonable expectation of privacy and would constitute a search for constitutional purposes. 

The constitutional question is not merely an exercise in counting cameras; the analysis should focus, ultimately, on the extent to which a substantial picture of the defendant’s public movements are revealed by the surveillance.  For that purpose, where the [automated license plate readers] are placed matters too.  [Automated license plate readers] near constitutionally sensitive locations—the home, a place of worship, etc.—reveal more of an individual’s life and associations than does an [automated license plate readers] trained on an interstate highway.  A network of [automated license plate readers] that surveils every residential side street paints a much more nuanced and invasive picture of a driver’s life and public movements than one limited to major highways that open into innumerable possible destinations. For while no [automated license plate readers] network is likely to be as detailed in its surveillance as GPS or CSLI data, one well may be able to make many of the same inferences from [automated license plate readers] data that implicate expressive and associative rights.

Commonwealth v. McCarthy, 484 Mass. 493, 506 (2020).

The Supreme Judicial Court concluded that, while the defendant has a constitutionally protected expectation of privacy in the whole of his public movements, an interest which potentially could be implicated by the widespread use of automated license plate readers, that interest is not invaded by the limited extent and use of the technology in this case.  The cameras in question here gave police only the ability to determine whether the defendant was passing onto or off of Cape Cod at a particular moment, and when he had done so previously.  This limited surveillance did not allow the police to monitor the whole of McCarthy’s public movements, or even his progress on a single journey.

McCarthy lost his challenge, in the end, because the data produced by four cameras at fixed locations on the ends of two bridges did not expose too much information, including any expressive and associative rights.

The McCarthy case, however, suggests that data collected by parking enforcement, especially where the automated license plate reader system regularly and repeatedly captures data showing the travel of a certain car could violate the Fourth Amendment. 

Return to Case Results
Return to Criminal Defense page