A federal appeals court ruled Wednesday that law enforcement can legally scan or swipe a seized credit card—in fact, it is not a Fourth Amendment search at all, so it doesn’t require a warrant.

In the 8th Circuit Court of Appeals’ 15-page opinion, swiping a card does not constitute a physical search, as the magnetic stripe simply contains the same information obviously visible on the front of the card. Plus, the defendant, Eric-Arnaud Benjamin Briere De L'Isle, couldn’t have had a reasonable privacy interest in the card, the court concluded, because he would have tried to use it when he tried to buy something, thereby giving up privacy interests to a third party (the issuing bank).

According to court records in United States v. De L’Isle, the case began in June 2014 when Eric-Arnaud Benjamin Briere De L'Isle was driving westbound on I-80 and was pulled over by a Seward County, Nebraska, sheriff’s deputy.

The deputy, Sgt. Michael Vance, pulled over De L’Isle (also known as “Briere”) for following too close to a tractor-trailer. As Sgt. Vance approached the car, he noticed the distinct “odor of burnt marijuana” coming from within the car, and he observed three air fresheners hanging from the rear-view mirror. After questioning De L’Isle, Sgt. Vance suspected that the driver might have drugs, so he deployed his drug-sniffing dog.

While no drugs were located, the law enforcement agent found and seized:

…51 credit, gift, and debit cards in a duffel bag located in the vehicle’s trunk. Ten of the cards were American Express credit cards, all bearing Briere’s name, with different account numbers embossed on the fronts of the cards. A number of the debit and gift cards also had account numbers embossed on them, but none bore Briere’s name. Some of the cards were in wrapping utilized by the issuing company to display the cards in retail stores.

Later, upon further investigation by the Secret Service and the Department of Homeland Security, “The agents discovered the magnetic strips on the back of the 10 American Express credit cards in Briere’s name contained no account holder identification or account information which exists on legitimate American Express cards when they are issued.”

De L'Isle was indicted and eventually convicted of one count of possession of counterfeit devices. During trial, his attorney tried to raise the issue to suppress the search of the cards on the grounds that it violated the Fourth Amendment—an argument that was rejected by the judge but preserved on appeal. De L’Isle was eventually convicted and sentenced to 15 months in prison.

As the 8th Circuit concluded:

There may be an instance, with facts different from this case, where a court reasonably finds a legitimate privacy interest in information contained in the magnetic strip of a credit, debit, or gift card. In such a case, a motion to suppress may well be proper to further explicate the nature and character of privacy interests, if any, that may reside within the confines of these magnetic strips. However, here, where all of the information in the magnetic strip should have been identical to the information in plain view on the front of the card, and where the cards were lawfully possessed by law enforcement officers and established to be counterfeit, we cannot conclude that De L'Isle had a privacy interest warranting further investigation into potential Fourth Amendment protections.

It is still unknown whether the Secret Service or DHS used an Electronic Recovery and Access to Data (ERAD) Prepaid Card Reader as part of their investigation—which surfaced in the news on Thursday, as it is newly deployed in Oklahoma.

The federal law enforcement agencies did not respond to Ars’ request for comment.