Host Stephen Colbert appears on “The Late Show With Stephen Colbert” in New York on March 31. (Richard Boeth/CBS via AP)

When Stephen Colbert unleashed a vulgar joke about President Trump on his late-night show last Monday, some felt the comedian had crossed a line.

“The only thing your mouth is good for is being Vladimir Putin’s c— holster,” Colbert said of the president. The most vulgar part of the joke was bleeped when it aired.

#FireColbert soon began trending on Twitter, where many lambasted his joke as homophobic. The Federal Communications Commission reportedly received complaints about Colbert’s remarks.

However, it was only after FCC Chairman Ajit Pai acknowledged Thursday that the commission would review complaints about Colbert’s joke that the story spun out of control, according to media law experts.

Suddenly, the FCC had opened an “investigation” into Colbert, according to headlines in multiple news outlets. Under federal law, profane, indecent and/or obscene content is prohibited from being broadcast on TV or radio.

But such headlines are misleading because the FCC reviews every complaint it receives, said Andrew Schwartzman, a media law specialist at the Georgetown University Law Center.

“If somebody files something, of course the FCC has to look at it,” Schwartzman said in an email to The Washington Post. An FCC spokesman confirmed to The Post on Monday that the commission was not launching an investigation.

After making an oral-sex joke about President Trump and Vladimir Putin, there are calls from Trump supporters to fire late-night host Stephen Colbert. On May 3, Colbert acknowledged the haters, but he didn't apologize. (The Washington Post)

Even if there was one, the “Late Show With Stephen Colbert” airs, well, late enough that it is exempt from the FCC’s policies on profanity and indecency. The FCC defines indecent content as that which “portrays sexual or excretory organs or activities in a way that does not meet the three-prong test for obscenity.” Profane content “includes ‘grossly offensive’ language that is considered a public nuisance,” according to the commission.

However, these rules don’t apply to broadcast TV and radio shows that fall into a “safe harbor” period — airing between 10 p.m. and 6 a.m., ostensibly when children are not watching or listening. Colbert’s show airs at 11:35 p.m. Eastern.

Obscene content, on the other hand, is the most serious of the three FCC designations and prohibited by law no matter the time of day. Even then, “there is ZERO chance” that Colbert’s comments would meet the obscenity test, Schwartzman said. “What Colbert said, if run unbleeped, probably wouldn’t meet the test for indecency that applies before 10 p.m.,” he added.

For content to be deemed obscene, “it must meet a three-pronged test established by the Supreme Court: It must appeal to an average person’s prurient interest; depict or describe sexual conduct in a ‘patently offensive’ way; and, taken as a whole, lack serious literary, artistic, political or scientific value,” according to the FCC.

This three-pronged threshold for the FCC to find something “obscene” is so high that Schwartzman said he was hard-pressed to think of a successful obscenity case since the late 1970s.

Media lawyer David Oxenford agreed, calling the commotion over the FCC and Colbert “much ado about nothing” on his blog about broadcast law.

“If it’s legally obscene, it’s got to be really bad,” Oxenford told The Post. “It has to be pandering to the prurient interest, the sexual interests of the audience, and has no redeeming social significance. … It’s something that I don’t think the FCC to my knowledge has ever really been faced with.”

An FCC spokesman declined to comment beyond confirming that the commission was reviewing viewer complaints as standard operating procedure — not launching an investigation. He also pointed to the most recent instance the commission had fined anyone for indecent content: a case from 2012 involving WDBJ, a TV station in Roanoke.

During one of its 6 p.m. newscasts that summer, WDBJ accidentally broadcast a brief shot of someone engaging in a sexual act in a report about a former porn star who had joined a local volunteer rescue squad. The sex act was displayed in a box to the right of the main report and appeared for less than three seconds, case records stated.

Was it indecent? Yes, the FCC ruled in 2015. But obscene? No.

That’s because, in the context of the broader newscast, the content did not, as a whole, “lack serious literary, artistic, political or scientific value.” And that porn broadcast during the 6 p.m. news did not qualify as obscene underscores how high the obscenity standard is, said Jack Goodman, the attorney for WDBJ in that case.

“Not only does it have to be a very explicit depiction of a sexual act, the entire work — which would in this case be the Colbert show — has to have no artistic or cultural merit,” Goodman told The Post. “It’s ludicrous to think that [Colbert’s joke] could be ‘obscene.’ … Just merely suggesting an act of oral sex wouldn’t get you there.”

That said, Pai was far less definitive in his remarks to Philadelphia radio station WPHT-AM.

“I have had a chance to see the clip now and so, as we get complaints — and we’ve gotten a number of them — we are going to take the facts that we find, and we are going to apply the law as it’s been set out by the Supreme Court and other courts, and we’ll take the appropriate action,” Pai told the radio station.

“I don’t want to prejudge whatever determination the FCC might make,” Pai added.

Goodman said he was surprised by Pai’s public remarks. The FCC chairman must have known that the “Late Show” fell within the “safe harbor” period and was not subject to profanity or indecency rules, Goodman said. And if Pai had indeed watched the clip, he should have also surmised that it had little chance to meet the obscenity standard, Goodman added.

And yet Pai’s statement gave the impression that the FCC’s review might find something serious, Goodman said.

“By treating this as a serious question, which it’s not, the commission is essentially putting pressure on broadcasters over something that nobody applying the standard could conclude,” Goodman said.

For his part, Colbert has remained unapologetic — though he did acknowledge Wednesday he would “change a few words that were cruder than they needed to be.”

“I have jokes; he has the launch codes,” Colbert said of Trump then. “So, it’s a fair fight.”

Paul Farhi contributed to this report.

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