What happens when the news media catch the White House in a demonstrable lie? That depends entirely on whether they like the administration. If they loathe the administration, it’s front-page news. If they like it, they spike the story. As Momma used to remind us, if you can’t say something nice, don’t say anything at all. What a great motto for reporters.

That is exactly what the national media have done to an important story about the White House’s intimate working relationship with MIT professor Jonathan Gruber, who helped craft the Affordable Care Act. You may remember Gruber from his infamous videotapes, the ones in which he called the American public too stupid to understand the law. He added their stupidity was helpful to Obama, Pelosi, and Reid in passing the law.

The Obama administration snapped into action. At a press conference, the president noted that Gruber was not employed by the White House and said flatly that he had not played an important role in drafting the law. Nancy Pelosi said the same thing. On background, senior White House officials reinforced the story. They vaguely remembered somebody named Gruber or Goober or something but, fortunately, he played only a marginal role in health care. Thanks for asking. Next question?

Now, this may surprise you, but it turns out the White House knew Gruber very well and knew he played a crucial role in the health care bill. The White House simply decided to lie about it. Perhaps they agree with Gruber’s judgment about your intelligence.

How do we know about Gruber’s role? Not because the White House released any documents, not because the media dug into it, but because the House Oversight Committee, chaired by Utah Republican Jason Chaffetz, got MIT to turn over the relevant emails. There were 20,000 pages of emails back-and-forth between Gruber and the White House in the crucial months when the bill was being crafted and passed.

The Wall Street Journal just revealed the news about the Oversight Committee getting these emails in a major story. The key points are that Gruber was deeply involved in crafting the health care law, he worked very closely with the White House, and, when he became a political liability, the president and his senior aides simply lied about it.

Is that a big story? Not if you are a national TV network or major U.S. newspaper. Except for the Wall Street Journal, they maintained radio silence. Not a peep.

A search of the New York Times shows zero hits for “Gruber” this week. All the News That’s Fit to Print? The Washington Post has one hit, a brief comment by an online opinion columnist. Regional newspapers like the Chicago Tribune: zero. It was covered on Fox’s morning show and, in a very revealing exchange, on MSNBC’s Morning Joe. The network shows – Good Morning America, the Today Show, and CBS This Morning – have eight hours of air time but did not mention it at all. Zilch. They could have squeezed it in without shortchanging the Kardashians or Brian Williams’ landing on the moon.

What happened on Morning Joe was fascinating. One of the hosts, Mika Brzezinski, called attention to the Journal story. Her co-host, former GOP Rep. Joe Scarborough, followed up. Turning to Mark Halperin, who is the co-managing editor of Bloomberg Politics and a former senior reporter at Time, Scarborough asked if the story was inconsistent with White House statements. “I owe my Republican sources an apology,” Halperin said, “because they kept telling me he [Gruber] was hugely involved, and the White House played it down.”

Then Scarborough asked the money question: “Did the White House lie about that?”

“I think they were not fully forthcoming.”

That answer did not come from a White House official or a Democratic operative. It came from a big-time reporter. And not just any reporter. It came from a reporter to whom the White House had deliberately lied in background briefings. Does he call them out? Nope. He spins for them.

Halperin’s circumlocution shows the rot that pervades America’s mainstream media. He cannot bring himself to say more than “they were not fully forthcoming.” Morning Joe’s panel of Democratic stalwarts, including Howard Dean, actually laughed out loud. When they were asked the same question—did the White House lie?—they kept laughing and said “they were not fully forthcoming.” I guess the joke’s on us.

As lies go, it’s not a huge one. It’s not like saying, “If you like your doctor, you can keep your doctor. If you like your health insurance, you can keep your health insurance. Period.” That wasn’t just fraud; it was fraud that played an essential role in passing Obamacare. The president knew it was false when he said it, and he said it repeatedly.

Still, the latest Gruber episode tells us something troubling and important. If the media share the White House’s political views, then journalists and editors will refuse to do their essential job: truthful reporting. They will spike the story. On the same spike, they impale what is left of their reputations.