Temporary license plates must be in the same location as permanent tags, not elsewhere on the vehicle, the Colorado Court of Appeals ruled for the first time on Thursday.

Colorado law requires that, as of July 1, 2016, the Department of Revenue must manufacture temporary tags that comply with requirements for permanent rear license plates. Among the features, rear plates must be no lower than 12 inches from the ground, clearly visible, and mounted on – or within 18 inches of – the rear bumper.

“In our view, the only reasonable reading of these statutory provisions is that temporary plates must be fastened in the same location as the permanent rear license plate,” wrote Judge Michael H. Berger for the three-member appeals panel.

A spokesperson for the Colorado State Patrol said the agency will evaluate the decision to determine what, if anything, will change for law enforcement.

“We have to look more into things before we issue any training updates to our members,” said Sgt. Blake White.

The decision arose from the case of Andrew James Hayes, who was the passenger in a car that police stopped for lack of a visible license plate. Upon pulling over the vehicle, the officer saw a temporary tag in the rear window and subsequently learned Hayes had an outstanding warrant.

During booking, police found a plastic bag with methamphetamine. Prosecutors charged him with possession of a controlled substance, but Hayes claimed the evidence constituted a violation of the Fourth Amendment’s prohibition on unreasonable searches and seizures. The officer, Hayes argued, lacked reasonable suspicion to continue the traffic stop after he saw the temporary plate because its placement did not violate the law.

In 2006, the U.S. Court of Appeals for the 10th Circuit, based in Colorado, ordered suppression of evidence in a similar circumstance, in which a Kansas state trooper found cocaine in a vehicle he pulled over for not being able to read the Colorado temporary license plate in the rear window. The ruling came 11 years after the Colorado Supreme Court reached the same conclusion involving a traffic stop in El Paso County.

However, those cases pertained to the visibility of the license plates. As Berger observed in Hayes’s case, the “question presented here is whether the law in effect at the time of the stop required the temporary plate to be affixed in the same location required for a rear license plate.”

The trial court denied Hayes’s motion and a jury convicted him. In deciding the vehicle in which Hayes was riding had improperly placed the temporary plate, the appellate panel upheld the constitutionality of the police stop and, therefore, Hayes’s conviction.

Judge Neeti Vasant Pawar agreed with the conclusion, but wrote separately to say the law’s wording is slightly ambiguous.

The language, she explained, “tells the DMV how to make temporary registration number plates; it says nothing about how or where vehicle owners or drivers must display them.”

However, in looking at the 2015 change in the temporary plate law, Pawar discovered the bill summary described an intent for temporary tags to go on “the rear of the vehicle where permanent license plates are placed.” She therefore concluded the law change also created an obligation for drivers to place the temporary plates accordingly.

The case is People v. Hayes.