When Craig Caldwell wanted to sublet a space to a fellow restaurant owner, his landlord turned the deal down. He was so shocked at the reason she gave that he used his cell phone to record two conversations with her.

His landlord said, find an "American person," according to the recordings, which have been shared exclusively with KUNC.

The recordings, which are part of a discrimination lawsuit, add to rising number of incidents and complaints about racism, bigotry, hatred and other bias across Colorado in the last two years -- and a national trend where events are captured by cell phones.

Caldwell, who runs White Fence Farms, a Denver-area chicken restaurant, recorded his landlord, Katina Gatchis, in December at the liquor store she runs in Capitol Hill.

Caldwell asked Gatchis: "You need an American person?"

Credit Michael de Yoanna / KUNC / KUNC The space where White Fence Farm restaurant closed remains vacant in Denver's Capitol Hill neighborhood.

"American person, I need," Gatchis replied, "good like you and me."

When Caldwell closed a corner store version of White Fence Farm at 9th Avenue and Corona Street in Denver, he found a team to take over in a sublet -- the Khans, who own Curry N Kebob in Boulder. They're Muslim and of Bangladeshi descent.

"They bring all the Muslims from the Middle East and then I have a problem around here," Gatchis told Caldwell on tape. "Bomb, boom. Bomb, boom."

She added, "This kind type, they are very dangerous, extremely dangerous."

The tapes are at the center of a lawsuit filed in Colorado District Court in Denver. It argues that it was unconstitutional for Gatchis to deny Caldwell's request to sublet to the Khans. It says that Gatchis discriminated against the Khans' religion, race and national origin.

"This type of discriminatory behavior, these turnaways, are part of our legal history -- it has been thoroughly examined and wholeheartedly rejected," said one of the attorneys for Caldwell and the Khans, Qusair Mohamedbhai, with the Rathod-Mohamedbhai law firm in Denver. "When minority communities are completely locked out from certain aspects of society, from commerce and business opportunities, it keeps an entire community down."

Gatchis, he said, has violated federal civil rights law that gives all citizens the same right enjoyed by white citizens to purchase, lease, sell, hold and convey real and personal property. He added that Gatchis' denial runs counter to state and city anti-discrimination laws.

Reached at her liquor store, Gatchis gave the phone to her son, who declined to comment, referring KUNC to defense attorneys. Only one of Gatchis' four defense attorneys, William Short, could be reached after several calls and emails went unanswered.

"Sir, I have a trial tomorrow. I have no comment. Thank you," Short said via phone, hanging up before any questions could be asked about the case.

In court filings, Gatchis denies the allegations that she wrongly discriminated against Caldwell and the Khans. She also denied all the statements on Caldwell's tapes.

'More emboldened to act out'

In a small strip mall in Boulder, a sign at Curry N Kebob advertises a lunch special for $8.95.

Inside the tiny kitchen, a cook hovers over a deep fryer. Another stirs pots on a stove. Co-owner Rashad Khan says he aims to stay true to the family recipes.

"We even make our own cheese and yogurt from scratch," Khan said.

His accent is American and he immigrated to the United States when he was a boy. His dog is named Ralphie, after the University of Colorado's mascot because that's where he went to college.

"I bleed black and gold," Khan said, a reference to CU Boulder's team colors.

After college, he went went into corporate life - IT, sales and management - but decided to return and help transform his family's Indian restaurant into something with a more fast-casual vibe. Curry N Kebob, he said, is ready to branch out. Denver's diverse Capitol Hill, a neighborhood he knows well and loves, would have been perfect.

"It made all the business sense in the world," Khan said. "There 450,000 people within five square miles and the money is right there; people who have a certain amount of disposable income."

Credit Michael de Yoanna / KUNC / KUNC Craig Caldwell and Rashad Khan standing outside of Curry N Kebob in Boulder.

Caldwell agreed. The Khans financials show they could afford the risks and, even if they ran into trouble, Caldwell would be responsible.

That still wasn't enough to sway Gatchis, the landlord.

On tape, Caldwell told Gatchis of Khan, "He's stronger [financially] than I am."

"No he's not," Gatchis said.

"Yes he is," Caldwell replied.

"You're American," Gatchis told Caldwell. "You know that? Lot of difference. You know that?"

"Well, I don't know about that," Caldwell replied.

"Yes," Gatchis told him.

"So if I get anybody as long as it is not a Muslim, I'd be OK?" Caldwell asked.

"Yes," Gatchis replied.

Claims of discrimination in Colorado have been rising in the last two years. The regional Anti-Defamation League, for instance, has tracked a more than threefold rise in defamation cases against Jewish people since 2015. There were 57 in 2017.

Scott Levin, director of the ADL's Colorado, Wyoming and New Mexico region sees those cases as a bellwether for the experiences of other minorities.

"What seems to have changed in the last two, three years is that people have felt more emboldened to act out on their bias and bigotry," Levin said. "In a way, it seems people have been given more permission to do that than they might have otherwise been in the past."

Since 2015, there has also been a notable rise in complaints filed with the Colorado Civil Rights Division alleging discrimination based on race, color, national origin and religion, among other categories. For instance, racial discrimination complaints went up from 198 cases in the 2014-15 year to 296 in 2016-17. In the same period, complaints about creed or religion went up from 44 cases to 72.

The division tracks employment, housing and public accommodations claims, but not specific scenarios like whether a restaurant owner has been denied access to a space because of alleged discrimination.

The case involving Caldwell and the Khans isn't being investigated by the division. Instead, it will play out in court -- perhaps before a jury next year.

Credit Michael de Yoanna / KUNC / KUNC Attorneys Qusair Mohamadbhai and Iris Halpern

Iris Halpern, a longtime discrimination lawyer on the case with Rathod-Mohamedbhai firm, said what makes the case so unique is Caldwell's recordings.

"With the tapes that Craig Caldwell has, it's very obvious, and there's direct evidence, that Gatchis discriminated against the Khans and also affected Craig Caldwell because of their race and national origin and religion," Halpern said. "Katina Gatchis felt that she's able to define who is American and who is not."

Both Caldwell and Khan say they are ready to fight in a case that could go to jury trial in 2019.

"It was 50 years ago today that I went into the U.S. Army," Caldwell said. "I got drafted and it was 1968. That's the reason you go in. You fight for your country. You go to Vietnam and stuff like that is, you know, so these kinds of things don't happen. I mean this is America and this is unacceptable."

Khan says the most upsetting part of hearing the recording of Gatchis, is the part where she says she wants an American to sublet the space.

"Somehow I was less of an American," Khan said. "You know, I've been here since I was, like, 11 years old."

He added, "At the end of the day, I'm an American. That's who I am."