Mignon Clyburn, acting chairwoman of the Federal Communications Commission (FCC). Obama’s nominee Tom Wheeler is expected to be sworn in as the new chairman next Monday. (Andrew Harrer/Bloomberg)

Eight years ago, Mignon Clyburn was feuding with her sister about their ice cream and popcorn shop in Charleston, S.C. That’s when their father, James Clyburn, one of the most powerful lawmakers in Congress, forced the sisters to sit down at a table, close the door and stay in the room until they worked out their differences.

Facing her sister made it harder to walk away from the business and further strain the close-knit family. The strategy worked, and it was a lesson Mignon Clyburn brought to her six-month stint as interim chairman of the Federal Communications Commission, which wraps up next week.

Four years ago, Clyburn arrived in Washington as a regulatory newcomer to take a seat on the FCC. She faced immediate skeptics because of her high-profile father, a Democrat and former House majority whip. In her six months leading the FCC, she has pushed through consumer-friendly regulations to reform prison phone rates and to provide more access to technology in rural areas. The regulations, some industry experts note, are modest in their scope compared with controversial policies the agency has taken on, such as net neutrality.

But the 51-year-old commissioner says those policies are significant because they directly affect consumers, particularly minorities, low-income families and rural residents.

“These are my people,” she said in a recent interview. “My duty is to empower communities, particularly those like mine that are often overlooked.”

President Obama’s pick for chairman, Tom Wheeler, is expected to be sworn in Monday and to turn the agency’s focus to the nation’s biggest telecom issues: launching a mobile airwaves auction and switching Americans from phone lines to wireless and broadband Internet connections.

Clyburn will remain a member of the FCC and said she will work with her fellow Democratic chairman and maintain a focus on consumer protections.

She took up the rules for prison phone rates even before her stint as interim chairman by reviving a decade-old petition that had been largely ignored by other staff, industry observers say. The new rules will dramatically reduce the cost of prison phone calls, which had skyrocketed to as much as $11 for 15 minutes.

Clyburn met with family members of inmates to hear their stories. In November 2012, she accepted a petition with 40,000 signatures outside the agency in Washington and spoke to protesters rallying for the reforms.

“This is an aspect of the FCC that actually affects individuals and consumers and she didn’t want to see that effort go wasted,” said Lee Petro, a lawyer with Drinker Biddle & Reath who has worked pro bono to overhaul prison phone call rates.

The former South Carolina public utilities commissioner also passed an order this month that forces all carriers to use the same technical standards for mobile broadband networks. That blanket standard, first proposed four years ago, would give small and rural carriers the ability to offer consumers access to the full set of devices that only the biggest carriers such as AT&T now provide on their networks.

Major wireless firms were against the interoperability order, but Clyburn called consumer groups and wireless carriers to an eighth floor conference room at the FCC to negotiate a deal.

“It’s a Clyburn basic: sit there, work it out, do not leave until it’s done,” she said.

The rule, telecom experts say, proved her political and intellectual grit at an agency often pressured by billion-dollar businesses to keep the status quo.

“That deal took serious arm-twisting of big carriers,” said Gigi Sohn, president of public interest group Public Knowledge.

Clyburn acknowledges her privileged political family but still sees herself as an outsider.

“I’m the most unlikely person to be serving in this capacity. I’m not your typical commissioner in that I’m not an inside-the-Beltway Washington attorney in the FCC bar circles,” she said.

Clyburn prefers the culture of her hometown, Charleston, to Washington. She goes home at least once a month where her mother, two younger sisters and a close extended family reside.

In Washington, she lives in the same apartment building as her father. But she doesn’t see him more than a few times a month at most. At first, she turned to him for advice. Now, she said, he will come to her for guidance on telecom and technology policy issues that cross his desk.

Clyburn demurs when asked about future political aspirations.

“I’ve always been led by others who can see things clearer than I can,” she said. “But public service will always be part of who I am.”

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