Referring to erroneous reports that the Trump campaign received a file of hacked emails ten days before it was posted on Wikileaks in September 2016, the Intercept’s Glenn Greenwald wrote this weekend that last Friday was “one of the most embarrassing days for the U.S. media in quite a long time.” While Greenwald’s rhetoric about the American press is often harsh even by leftist-intellectual standards, it’s hard to say he is wrong about this. Let’s review:

• CNN reported Friday morning that Donald Trump Jr. and his father received an email on Sept. 4, 2016 which would have allowed them to access hacked Democratic emails that weren’t posted by Wikileaks until Sept. 13. CNN’s report was based on “multiple sources,” and would have been huge news—evidence of the Trumps being given an early look at material that, it’s believed, was originally obtained by Russian intelligence operatives.

• CBS then reported that it had “confirmed” CNN’s report.

• So did NBC, citing “two sources.” But …

• The Washington Post reported at about 1 p.m. Friday that the email in question was received on Sept. 14, which means it was just a link to documents that were already public.

• CNN, CBS, and NBC all then reported that the Post was right about the date—but none said that the error had been made on their end. CNN and CBS said their sources got it wrong; NBC’s post blames CNN. (The Post actually had the email in question, but CNN and CBS—and presumably NBC, though I don’t think they’ve said so outright—were relying on descriptions thereof when they made their initial reports.)

None of the outlets disclosed anything about the identities and/or motivations of the sources—and there are supposedly at least two of them!—who made such a consequential error of reading comprehension. Nor did any of them provide further information when I contacted them this afternoon asking whether they’d found out anything more about last week’s mysterious, sudden D.C.-wide inability to distinguish between 4 and 14.

What happened? It seems like there are six possibilities:

• The outlets were relying on solid sources who all made the same honest mistake.

• The outlets were relying on secondhand sources who were just B.S.-ing the whole time and repeating a bad story that had gotten to them via a game of national security telephone.

• The outlets were relying on bad-faith sources who were intentionally trying to make the mainstream media look bad. (The Sept. 14 email in question is in the possession of the House Intelligence Committee; maybe some Trump loyalists on the committee pulled a James O’Keefe.)

• Only one source ever actually misread the date of the email; the rest of the sources that “confirmed” the story simply confirmed the existence of the email, not when it was sent. These “confirming” sources were then all conflated together by outlets overeager to rush out a big scoop.

• “Fake news.” (As in, the reporters made all of it up to GET TRUMP.)

• Aliens.

My personal guess is it’s No. 4, but without more transparency from the outlets that got the story wrong, many skeptical observers—especially those on the right—will naturally lean toward No. 5 and No. 6. That’s just the country we live in now, folks!