Another reported that in twelve years working for her previous boss, he "never took a closed door meeting with me. ... This made sensitive and strategic discussions extremely difficult."

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Male staffers said they'd also seen some female aides barred from solo meetings with the boss, and that they benefited in some instances from the exclusion of their female colleagues in high-level meetings, at receptions with major Washington powerbrokers, and just in earning a little more face time with their bosses.

For these women, the lack of access has meant an additional hurdle in their attempts to do their jobs, much less further their own careers. And in many instances, it forced them to seek employment in other congressional offices.

The issue is hardly the norm. Numerous staffers contacted for this story, both male and female, said they had never experienced or even heard of such a policy. But those who do employ these policies could have a legal issue.

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Debra S. Katz, an employment discrimination attorney in Washington for thirty years, said she'd never heard of a such a policy being employed in the private sector, but added that "the practices are clearly discriminatory in my view."

Katz worries that limitations on what female staffers could do in a congressional office compared to male staffers would hinder hiring decisions. And even for women who do get hired, the lack of one-on-one time could prevent them from moving up within their offices. "You're not being perceived as a professional," Katz said.

"So much happens in creating trustful relationships and if you can't develop a trustful relationship where you're having some one-on-one time, as the men apparently are getting -- I can see many reasons why this is a terrible idea, terrible in the sense of discriminatory," Katz added, calling the practice "clearly unlawful."

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One female House Republican aide said that when she worked in the Senate, she frequently staffed her male boss at events both on and off the Hill. But that came to an end when the office chief of staff said that she was appearing in the background of too many photos with the senator. "I remember our chief saying that it was not appropriate," the staffer said.

When she gets together with other female Hill staffers, she said, the issue comes up a lot. "It's definitely something that a lot of women on the Hill experience and not necessarily because the boss is creepy or that it's protecting her," the House Republican staffer said. "It's to make situations not seem untoward."

Nonetheless, the aide said, the policy was still difficult for her to accept. "It's demeaning for the staffer. It prevents our access," she said. "If you're serious about your career you're not going to go around screwing your boss."