Our firm previously examined a Sixth Circuit decision casting doubt on the practice of “chalking”—using chalk to mark the tires of parked vehicles to track how long they have been parked—to enforce parking restrictions in unmetered public parking spaces.  In that case, Taylor v. City of Saginaw, the Sixth Circuit concluded that chalking can give rise to a claim under 42 U.S.C. § 1983 for an unreasonable search in violation of the Fourth Amendment. In particular, the Sixth Circuit held that chalking is a “search” within the meaning of the Fourth Amendment under a common-law trespass theory revived by the U.S. Supreme Court in United States v. Jones  because the City made intentional physical contact with the plaintiff’s vehicle in an attempt to obtain information. We argued that California public agencies should take heed of the Sixth Circuit’s decision but could resist it on several grounds, including that City of Saginaw is not binding law in the Ninth Circuit and did not resolve the constitutionality of chalking in the Sixth Circuit on a fully developed record because it merely reversed the district court’s grant of a motion to dismiss.
On New Year’s Eve, however, the Ninth Circuit may have closed the door on one of those arguments. In United States v. Dixon , the defendant sought to suppress evidence of drugs found in his car and apartment on the ground that his Fourth Amendment rights were violated when an officer surveilling him used a set of keys the defendant had dropped on the ground to unlock the defendant’s vehicle and enter his apartment.  The Ninth Circuit held that “the insertion of a key into a minivan’s lock constituted a search within the meaning of the Fourth Amendment.”  The court reasoned that when the officer inserted the key into the minivan’s lock, he “physically intruded into a constitutionally protected area” “for the express purpose of obtaining information, specifically to learn whether [the defendant] exercised control over the minivan.”  The court also explained that its conclusion was “in accord with that of [its] sister circuits” that “have similarly concluded that such physical intrusion constitutes a search.”  In doing so, the Ninth Circuit cited the Sixth Circuit’s decision in City of Saginaw approvingly with a “cf.” introductory signal and the following parenthetical explanation: “finding city’s chalking of tires to determine how long a vehicle had been parked in the same location constituted a search under Jones.” 
Notably, however, Dixon’s embrace of City of Saginaw does not entirely close the door on the practice of chalking for California municipalities. While the decision means that the practice likely constitutes a “search” under the Fourth Amendment, the decision does not speak to the reasonableness of that search in the context of chalking.  This is particularly the case once an action challenging the practice of chalking moves beyond the pleadings and the public agency can present evidence to support one of the many exceptions that we previously explained could justify the practice of chalking:
In particular, California public agencies may argue that chalking is reasonable under the “special needs” exception to the warrant requirement. The Supreme Court has “upheld certain regimes of suspicionless searches where the program was designed to serve ‘special needs, beyond the normal need for law enforcement’” and has “allowed searches for certain administrative purposes without particularized suspicion of misconduct, provided that those searches are appropriately limited.” In particular, the Court has approved the “warrantless administrative inspection of premises of ‘closely regulated’ businesses,” “administrative inspection of fire-damaged premises to determine cause of blaze,” “administrative inspection to ensure compliance with city housing code,” and “suspicionless seizures of motorists at a fixed Border Patrol checkpoint designed to intercept illegal aliens . . . and at a sobriety checkpoint aimed at removing drunk drivers from the road.” The Court has even “suggested that a similar type of roadblock with the purpose of verifying drivers’ licenses and vehicle registrations would be permissible.” 
Indeed, at least one District Court in the Ninth Circuit and the District Court for the Eastern District of Michigan on remand from the Sixth Circuit’s decision in City of Saginaw have already applied these rationales to uphold municipalities’ chalking practices at summary judgment. 
For example, in Verdun v. City of San Diego , the District Court had previously denied the city’s motion to dismiss after agreeing that chalking constituted a “search” under the Fourth Amendment because “the Court deemed it improper, at the motion to dismiss stage, to dismiss Plaintiffs’ entire action pursuant to a warrant exception based only on the facts pled.”  But on January 4, 2021, the Court granted the city’s motion for summary judgment, holding that the city’s “chalking program is a reasonable administrative search, and therefore passes constitutional muster under the Fourth Amendment.” The Court reasoned that “the primary purpose of tire chalking at a programmatic level is the administrative enforcement of parking regulations—not a general interest in crime control or detecting evidence of criminal wrongdoing.”  As a result, the Court explained, the chalking program “amounts to an administrative search that is permissible under the Fourth Amendment, so long as it is reasonable.”  And the chalking is reasonable, the Court concluded, because the city’s interest in chalking outweighed the “brief and minimal intrusion upon [plaintiffs’] privacy interest in the exterior of their vehicles”:
Here, the City’s interest in the search is legitimate and important because tire chalking furthers the administrative purposes of preventing widespread noncompliance with parking regulations, which in turn prevents cruising, double parking, and illegal parking. As the parties concede, cruising, double parking, and illegal parking lead to increased traffic congestion, which causes major negative public safety, environmental, and business impacts on the City of San Diego.
. . . .
The undisputed facts in this case simply does not support a finding that the City’s nearly 50-year practice of placing a short, impermanent chalk mark on a vehicle’s tire treads in furtherance of the City’s parking regulations amounts to unreasonable or arbitrary government intrusion. As the record makes clear, the parking officers must mark every vehicle parked in City-owned spaces, and do not have discretion over which vehicles to mark. 
Even in the Sixth Circuit, the same District Court whose dismissal on the pleadings the Sixth Circuit had reversed in City of Saginaw subsequently granted the City’s motion for summary judgment on remand. Similar to the District Court in Verdun, the Court held that the city’s practice of chalking tires did not violate the Fourth Amendment because it fell within the “administrative search exception.”  The Court relied on cases permitting warrantless searches of commercial businesses, searches and seizures of vehicles near the border, and seizures of vehicles at sobriety checkpoints.  The Court explained:
The City argues that regulating parking is an important Government interest because it promotes safety and order on its roadways and ensures that multiple people can access downtown businesses. Regulating parking involves more than simply issuing a ticket and placing it on the vehicle. It may also involve other methods, such as chalking a vehicle’s tire to notify the driver that their parking time is being monitored. Chalking may lead to more effective parking regulation because it reminds drivers to move their vehicles before their allotted time has expired. Without the chalk mark reminder, some drivers may forget that their time is being monitored. Their vehicles would remain in parking spots beyond their allotted time and prevent others from using the parking location. This prevents circulation of people who can frequent downtown businesses and requires increased effort and resources by the City to issue parking tickets. 
The Court concluded that “[t]he City’s use of chalk is reasonable because it is in the public interest and the ‘severity of the interference with individual liberty’ is minimal” since “[a] discrete chalk mark on a tire does not substantially interfere with a party’s individual liberty.” 
Taken together, these recent District Court decisions reveal a path forward for municipalities notwithstanding the Sixth Circuit’s conclusion (and the Ninth Circuit’s apparent agreement) that chalking amounts to a search. That path entails moving for summary judgment on a fully developed evidentiary record showing that chalking is part of a regulatory scheme in furtherance of an administrative purpose that is no more invasive than necessary to serve that legitimate and important administrative purpose.