A majority of employees have left the leading U.S. transgender advocacy group amid a failed attempt to oust its leader, with many expressing frustration over the organization's lack of minority hiring and outreach.

The exodus at the National Center for Transgender Equality takes place as the nonprofit group prepares for two monumental events in 2020: the presidential election and the world's largest survey of transgender people.

The Washington-based center's staff is down to eight people from a high of 21 at the start of 2019, Executive Director Mara Keisling said on Friday.

Keisling said the changes were related to a long-planned strategic overhaul of the group, which had grown rapidly and needed to modernize its operations, including the need to hire and retain more people of color. Employees who disagreed with the new direction were given the chance to accept buyouts, she said.

"We just needed a course correction and part of that was a generally new direction," Keisling said in a telephone interview.

As for the complaints about minority hiring and retention, she said, "We have significant racial justice and racial equity work to do. Almost every organization does."

The restructuring had begun well before staff members wrote a letter asking her and Deputy Director Lisa Mottet to resign within 18 months, Keisling said.

Employees said they had grown frustrated over the center's poor hiring of and outside advocacy for people of color and also raised concerns that the survey, a resource widely sought by researchers, journalists and the transgender public, was in jeopardy.

"We have seen a damaging level of staff turnover, including a starkly disproportionate number of people of color terminated, pushed out, or otherwise separating from the organization," read the letter signed by 10 members of the staff. The staff letter also praised Keisling for building the most formative transgender rights organization.

At the same time, the staff was attempting to unionize, an effort that Keisling said management "actively encouraged." Nonetheless, the Nonprofit Professional Employees Union filed an unfair labor practice complaint with the National Labor Relations Board on Friday, alleging the staff reductions were retaliation for that effort.

"This is just a classic form of union-busting," said Kayla Blado, president of the Nonprofit Professional Employees.

BREAKING: We filed an unfair labor practice charge against the National Center for Transgender Equality for union-busting! 💪🏼💪🏾💪🏿https://t.co/Cif5dPGGsv #1u — NPEU (@NonprofitUnion) November 15, 2019

Keisling has been at the top of the organization since it was founded 17 years ago, becoming a leading figure in transgender rights and a occasional guest at the White House under former President Barack Obama, a strong supporter of transgender rights.

But President Donald Trump has reversed many of Obama's pro-transgender regulations and banned transgender people from serving in the military. Transgender advocates have made defeating him in the November 2020 election a top priority.

Survey looming

In addition, the transgender center is due to conduct the 2020 U.S. Transgender Survey, which has been the world's most comprehensive study of transgender experiences by measuring discrimination in employment, housing, health care and education.

The study released in 2016 surveyed nearly 28,000 people, a notable sample size for a U.S. adult population that the UCLA Williams Institute estimates at 1.4 million.

Keisling vowed that the 2020 survey would be completed despite the turnover. Staff vacancies would be filled and funding for the group with an $3.5 million annual budget was uninterrupted, she said.

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