Following the state's recent legalization of marijuana, some Colorado drivers are now complaining that they're being singled out by police officers in other states simply because of their license plates. Legal experts say we could see a string of lawsuits, like the one filed by a 70-year-old retiree against the Idaho State Police.

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Darien Roseen argues that the police officer simply assumed there was marijuana in the vehicle, stopping him for no reason, searching his vehicle multiple times, and detaining him for questioning.

Here's more on the case from FoxNews.com:

Darien Roseen, a 70-year-old retiree, was returning home from his daughter's baby shower in Washington state in January when he was followed into an Idaho rest stop by a state trooper. A dash-cam shows Roseen -- who was driving a vehicle with a Colorado license plate -- being subjected to questioning over marijuana he did not have. His car was searched multiple times, and he was subsequently detained by police. On March 26, he sued the Idaho State Police for alleged license plate profiling as well as civil rights violations, according to the federal lawsuit obtained by FoxNews.com. "The dash cam video shows that the trooper would not have been behind our client had it not been for the plate he had on his car," Roseen's Idaho-based attorney, Mark Coonts, told FoxNews.com on Tuesday. According to the complaint, Idaho State Trooper Justin Klitch was parked in a median along Interstate 84 when Roseen's Honda Ridgeline truck with Colorado license plates was seen crossing from Oregon into Idaho. Immediately after Roseen passed Klitch's location, the trooper "pulled out from the Interstate median, rapidly accelerating to catch up with Mr. Roseen's vehicle," the lawsuit alleges. At the same time Klitch drove onto the highway, Roseen activated his turn signal and moved from the left lane into the right lane, proceeding to exit the highway into a designated rest area, Coonts said. Klitch followed the driver into the rest area -- much to his surprise -- and "accused Mr. Roseen of having something in his vehicle that he should not have in his vehicle," according to the lawsuit. "Trooper Klitch told Mr. Roseen that he would be calling a drug detecting canine to come and walk around the vehicle. After Mr. Roseen identified his possession of valid prescription medications, Trooper Klitch asked him, 'When is the last time you used any marijuana?', thereby assuming that Mr. Roseen had, in fact, used marijuana and inferring that he had used it recently," the lawsuit states. "Mr. Roseen did not commit any traffic offense while driving on the highway, and his exiting off of the highway into the rest area was not prohibited and he exited in a legal fashion." Roseen can be heard on the dash-cam telling the officer that, "I have not used marijuana in my entire life." Roseen and his truck were subjected to an hours-long search by Klitch and other officers and the man was later taken into police custody for further questioning. In the end, Roseen was handed a "citation for inattentive/careless driving," according to the complaint. The incident occurred less than a month after Colorado's recreational marijuana shops began legally selling the drug. In a statement on its website, the Idaho State Police claims it did not receive a complaint from Roseen prior to the filing of his lawsuit and said it "holds all of its employees to a high standard which includes following the Constitution of the United States and the laws and constitution of the State of Idaho."

On Fox and Friends this morning, we heard from our own legal expert, senior judicial analyst Judge Andrew Napolitano. He explained that Colorado residents cannot bring marijuana with them into other states that don't have the same laws, but added that police do not have "carte blanche" to stop Colorado drivers.

In the Roseen case, the judge said it will come down to "he said, he said," with the cop arguing he smelled marijuana and Roseen making the case that there was no way the officer could have smelled pot in his car.

The judge said he's concerned that police officers in other states will start looking for reasons to stop Colorado drivers, hoping to "luck out" and make a pot-related arrest.

"Guess what: they can't do that. You can't stop someone because of the license plate on their car. You can only stop someone because they've demonstrated some violation of the motor vehicle code by the manner in which they're driving," said Napolitano.

Watch the discussion above, and check back daily on Fox News Insider for all of Judge Nap's legal analysis!

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