Subway franchise owners Dallas Buttars, left, and Kristin Myers have sued the Layton Police Department in Utah for defamation. They speak here during an Aug. 9 news conference in Salt Lake City with their attorney Robert Sykes. (Rick Bowmer/AP)

After nearly 20 years in the food service industry, Kristin Myers was used to dealing with the occasional unsatisfied customer.

But last August, the Layton, Utah, business owner and her partner, Dallas Buttars, were thrown a bizarre curveball when a local police officer accused an employee of Myers’s Subway franchise of spiking his drink with THC and methamphetamine — allegations the local department repeated on a nightly newscast.

Within only a few days, however, investigators reversed course. According to a statement from the Layton Police Department released Oct. 11, additional drug testing was “unable to confirm that contaminates were in the officer’s drink.”

But by then, the damage had been done. According to a defamation lawsuit filed last week in U.S. District Court in Utah against the city and authorities, the police’s debunked claim sunk Myers’s business.

“This has been one of the worst years,” Myers told The Washington Post. “I’m in the store everyday, and I had several days were customers were coming in to give us the riot act. We also had people asking, ‘Can you put that special stuff in my sandwich.’”

Worse, Myers’s federal court complaint accuses police of purposely letting out misinformation when the evidence proved otherwise.

“They kept omitting key facts, leaving the false impression this officer had been poisoned,” Robert Sykes, the attorney representing Myers and Buttars, told The Post. “I’m not saying they should be sued for a faulty investigation. But part of the investigation doesn’t involve a press conference.”

On Aug. 8, 2016, the police officer went through the Subway drive-through in Layton, about 25 miles north of Salt Lake City. The officer bought a sandwich and a drink, according to the complaint, and after taking of sip from his drink said he felt “strange or ill.”

Back at the station, the officer told he colleagues that he believed “his drink had been adulterated with some kind of drug.” The other officers analyzed the drink with a “screening test” “involving an ion scanner,” the complaint stated.

“The test allegedly came back positive for methamphetamine and THC.” Trouble is, the test was well-known to have accuracy issues, the lawsuit said.

Even so, police suspicion fixed on the 18-year-old who was manning the drive-through window, referred to only as “TU” in the court records but identified by Fox 13 as Tanis Ukena.

“There was not a mean bone in his body, so we knew it right away, it didn’t happen,” Myers said. “It was incredibly shocking.”

The Subway owners agreed to allow police to investigate the possible poisoning on Aug. 8. The shop and employee were searched; drug dogs also sniffed the area, as well as Ukena’s car. Officers also watched surveillance video from inside the store.

Nothing pointed toward a possible crime. But Ukena was arrested and taken for questioning at the police station.

Later that day, a television news reporter from KSL — after receiving a tip from the police spokesman, Sgt. Clint Bobrowski — aired a report about the possible Subway poisoning. Bobrowski did an interview with the station outside the store between 5 and 6 p.m.

The piece, which ran on the 11 p.m. newscast, featured the department spokesmen saying “The drink tested positive for THC and methamphetamine.” Bobrowski also said “We can obviously assume” the drink was spiked “because he was a police officer in a marked vehicle but we don’t know for sure.”

“Our business causes us, a lot of us, to eat out every single meal, so something like this is incredibly terrifying,” Bobrowski said. “I don’t use the word ‘terrifying’ lightly. It’s scary.”

But the department actually should have known the poisoning was fake by the time the spokesman went on air, the complaint alleged. Not only did Bobrowski fail to acknowledge the investigation had proven nothing, the initial ion drug screening was known to have a “very high false positive rate for showing drugs when there are no drugs.”

Also, the officer was given two drug tests — one at 5:00 p.m., another at 9:00 p.m. — that both came back “negative for the presence of any drugs.”

Once the television news item went live, the impact was irreversible. According to Sykes, the Subway’s business was off 30 percent in the following weeks. Myers told The Post six employees quit.

“We were inundated with people that wanted to know what happened,” she said. “We got letters in the mail, anonymous ones, asking ‘How could you hire someone like that?’”

By Aug. 9, however, Layton City Police detectives admitted to the owners Ukena had done nothing wrong after again reviewing the surveillance video.

“The Layton Police Department would like to thank Subway for their complete cooperation,” the department said in an Oct. 11 news release. “The department would also like to express our appreciation for the patience of Tanis and his family during this investigation.”

The teenager filed his own lawsuit against the department, and last week Layton agree to settle the action for $50,000, the Salt Lake Tribune reported. Ukena is now serving on a Mormon mission.

The lawsuit filed last week by Myers and Buttars seeks to recoup the $17,000 loss tied to the alleged defamation, as well as additional damages of $250,000

Layton City Police Department’s Sgt. Paul Gardiner declined to comment on the lawsuit when contacted by The Post. Last week, Layton City Attorney Gary Crane told the Salt Lake Tribune his office was reviewing the case.

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