Minnesota Public Radio wanted to know why the government was holding up its license renewal for its flagship news station KNOW. The answer was surprising: A listener thought someone uttered the F-bomb on the air.

It turns out the listener misheard the word "flunked," which was broadcast on Terry Gross's Fresh Air in 2010, but the complaint to the Federal Communications Commission delayed the license until September 2013.

The FCC enforces federal laws against indecency, vulgarity and obscenity on broadcast TV and radio, and can issue big fines to companies that show "sexual or excretory organs" or air "profane speech." These days, when pornography and foul language are a click away on your cable remote or your smartphone, the FCC is still policing the public airwaves for swear words and glimpses of breasts and buttocks.

Federal courts eventually threw out the $500,000 in fines issued after Janet Jackson's 2004 Super Bowl wardrobe malfunction, ruling that the FCC wasn't consistently enforcing these kinds of "fleeting" violations. Yet the brief reveal on TV's biggest night resulted in thousands of complaints to the FCC and put pressure on the agency ever since to punish even momentary lapses.

The Janet Jackson episode was a "bellwether. It really shook people," said Tim Winter, president of the Parents Television Council, a watchdog of violent, obscene and other objectionable content. The group's membership soared, and Winter was invited to the White House in 2006 for the signing of a bipartisan bill to stiffen the penalties for violating obscenity and indecency restrictions.

"You're using the publicly owned airwaves to deliver your product for free to every home in the nation, and the only content regulation is that you have to wait till 10 o'clock to use the F-word and show nudity," Winter said. "That seems like a fair trade-off to me."

Broadcasters have pushed back, arguing that they lived in fear of being punished for blurted expletives and other inadvertent violations.

In 2013, the FCC proposed a change to its enforcement policy that it said would focus on more egregious cases. In a July 2013 letter to the FCC, MPR cited the profanity debacle in arguing for a higher bar for enforcement: "The KNOW license has now been in limbo for three years due to the misinterpretation/hypersensitivity of a listener, the backlog at the Commission, and the Commission's inability and failure to quickly dispense with such complaints."

But opponents, many organized by the Parents TV Council, swamped the FCC with objections that outnumbered comments of support by 1,000 to 1. About 3,000 came from Minnesotans, including one Baxter resident, who wrote: "Opening the door wider to these cancers will only hasten the destruction of America and her people."

The FCC refused a request for an interview, but a spokesman released this statement: "The Commission continues to take public comment regarding our rules related to indecency. That proceeding remains open and active."

Meanwhile, in March, the agency handed down the largest fine ever for a single broadcast from a TV station, $325,000, to WDBJ of Roanoke, Va. The news station had broadcast a story about a former porn star who had volunteered for a local rescue squad. The story included a screen shot of a website that featured, in a corner, an image of an erect penis.

The station has argued that the offending image wasn't visible in its editing equipment, which has since been replaced. National broadcasting groups have joined WDBJ in its fight against the fine, and hope this case will prompt the courts to step in and limit the FCC's power.

"The onerous fines that have been levied are ridiculous," said Jim du Bois, president of the Minnesota Association of Broadcasters.

Five months after the indecency fine, the already distressed station suffered a devastating blow when two of its reporters were murdered on live TV by a deranged, publicity-seeking gunman.

For all the brouhaha over filth on the airwaves, the number of complaints to the FCC about obscenity and indecency has actually plummeted, from 1.4 million in the year of Janet Jackson in 2004 to a mere 1,003 last year, FCC data show. Winter thinks it's a combination of a desensitized public, but also broadcasters knowing how to keep their content barely legal.

Still, Winter said, he thinks it's time for his group to examine the proliferation of "pixelated" nudity that's now showing up all over TV.

Contact James Eli Shiffer at james.shiffer@startribune.com or 612-673-4116. Read his blog at startribune.com/fulldisclosure.