The White House security specialist who told Congress that at least 25 officials received security clearances despite opposition from career staffers says she felt humiliated by what she considers an act of retaliation from her boss.

In an exclusive interview with NBC News, Tricia Newbold said her supervisor moved files to a shelf beyond her reach after she complained about the decision to grant security clearances over the objections of senior staffers.

"It was definitely humiliating," said Newbold, a manager in the White House’s Personnel Security Office, who has a rare form of dwarfism. "... But it didn’t stop me from doing what was right."

Tricia Newbold

Newbold's allegations were detailed in a letter that House Oversight Committee Chairman Elijah Cummings, D-Md., released Monday after she spoke to the committee in a private interview in March.

Newbold told the lawmakers that at least 25 applicants were granted security clearances despite “disqualifying issues” including concerns about foreign influence, conflicts of interest, drug use and criminal conduct, according to Cummings' letter.

NBC News reported in January that Newbold's boss, Carl Kline, approved Jared Kushner for top secret clearance after it was deemed unfavorable by two career security specialists. The pair had decided against recommending a clearance for Kushner after an FBI background check raised concerns about potential foreign influence on him, two sources familiar with the matter told NBC News.

Cummings subpoenaed Kline earlier Tuesday as part of the committee’s probe into the matter.

Speaking to NBC News, Newbold, an 18-year government employee, said a sense of duty fueled her decision to speak out to Congress.

"The protection of national security is not a Democratic issue or a Republican issue, it's an American issue,” said Newbold, who was not speaking in her official capacity. "And we as security professionals owe it to make all our recommendations in the best interest of national security."

Newbold, who is still employed with the Executive Office of the President, said she loves her job and the people with whom she works. She insisted that she's not disgruntled.

Asked if she was concerned about her livelihood, Newbold replied: "Absolutely, given the past retaliation, I'm always concerned, but it's important that we stand up to do the right thing no matter what."

Newbold filed a complaint with the Equal Employment Opportunity Commission last October alleging that Kline discriminated against her by moving security files to a new location that was beyond her reach.

"Not once, not twice, three times," Newbold said in the interview.

Newbold was later suspended without pay for two weeks for defying Kline, according to the suspension decision notice obtained by NBC News. The punishment was issued less than a week after the NBC News report about Kushner's security clearance.

Through his attorney, Kushner has repeatedly declined to comment on his clearance adjudication. In an interview aired on Fox News on Monday night, Kushner said: "Over the last few years that I’ve been here, I've been accused of all different types of things, and all of those things have turned out to be false."

Kline, who left his role at the White House and now works at the Pentagon, has not responded to repeated requests for comment by NBC News. But his lawyer, Robert Driscoll, provided a letter to the house committee saying he would fully cooperate with the investigation.

"The subpoena issued today does not change Mr. Kline’s willingness to appear before the committee to answer its legitimate questions truthfully," Driscoll said in a statement released Tuesday. "The facts will prove that he acted appropriately at all times. "