On Tuesday the Central Intelligence Agency’s LGBT employee resource group released a documentary highlighting the agency’s efforts in building a more inclusive working environment.

“Angle of Ascent” focuses on the cultural shift within CIA from the ‘Lavender Scare’ of the 1950s to the formation of ANGLE — the agency’s network for gay, lesbian, bisexual and transgender officers and allies.

In the documentary, several CIA employees recall a time when applicants were given polygraph tests and specifically asked about homosexual relations.

“One of the experiences in my life that made me supportive of the LGBT community was the polygraph answer early on when I was still a college student planning to come here,” said Justin Jackson, a former National Security Council director. “Feeling that a particular group was oppressed, was treated differently because of who they are. That polygraph has stuck with me all these years. Not because it was difficult to pass or because I didn’t like the polygraph but because I thought the question was inappropriate.”

For 20 years, ANGLE has worked to educate fellow CIA employees and members of other American intelligence agencies as to the importance of a workforce free from discrimination. The group has traveled to various Pride festivals around the nation in a visible capacity, including the 2015 Miami Beach Gay Pride.

In October, Out & Equal Workplace Advocates presented ANGLE with its first-ever “Excellence in Government Leadership Award.” Accepting the award at its Langley, Virginia headquarters, CIA Director John O. Brennan expressed a deep appreciation.

“It is difficult to overstate how heartening this progress has been to me,” Brennan said. “Indeed, one of the highlights of my tenure has been seeing the LGBT community blossom under the leadership of ANGLE and its cadre of devoted allies – a group of which I proudly belong. When I see people defying stereotypes, living life on their own terms, and staying true to who they are, I see more than kindred spirits – I see people who deserve my utmost respect and admiration. And that is what I see in the men and women of the LGBT community. It’s why they are such an inspiration to me.”

ANGLE’s birth came with the signing of executive order 12968 by former U.S. President Bill Clinton, which prohibited discrimination on the basis of sexual orientation in granting security clearances and access to classified information. In the era before Clinton’s executive order, closeted LGBT intelligence candidates were considered vulnerable to exploitation by foreign agents.

“It was kind of a Catch-22,” says ANGLE founder Tracy Ballard in the documentary. “If you were out you couldn’t be hired, but if you remained closeted you could be blackmailed so it was kind of this vicious little cycle of how we were going to treat individuals.”