Josh Hafner | USA TODAY

That bit of chalk left on your car's tire by a parking officer is unconstitutional, a federal court ruled Monday.

A three-judge panel took up the case of Alison Taylor, a Michigan woman who received 15 parking tickets during a three-year feud with a single parking officer, Tabitha Hoskins of the City of Saginaw.

Taylor's lawyer argued that the city's physical marking with chalk, done to note how long a vehicle is parked, amounted to searching without a warrant — a violation of the Fourth Amendment. The 6th U.S. Circuit Court of Appeals panel unanimously agreed.

The city "commences its search on vehicles that are parked legally, without probable cause or even so much as 'individualized suspicion of wrongdoing' — the touchstone of the reasonableness standard," the court's opinion states.

The Fourth Amendment protects against "unreasonable searches and seizures." And the city's chalking of cars "to raise revenue" does not qualify as a public safety concern that could allow a search without a warrant, the court said.

The court's decision affects Michigan, Ohio, Kentucky and Tennessee.

"Trespassing upon a privately-owned vehicle parked on a public street to place a chalk mark to begin gathering information to ultimately impose a government sanction is unconstitutional under the Fourth Amendment," Taylor's lawyer, Philip Ellison, said in a court filing reported by NPR.

Ellison said that covertly marking a tire with chalk is not unlike police secretly putting a GPS on a car without a warrant, according to the Associated Press.

Now the case will return to U.S. District Court in Bay City, Michigan.

“We don’t think everyone deserves free parking,” Ellison told the AP, which reported that Ellison wants the case certified as a class-action to refund those so ticketed by the city.

University of Southern California law professor Orin Kerr called the case "fascinating" on Twitter, but had a simple solution for parking officers: Just take a photo.

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