The Washington Post has joined The New York Times in issuing a correction to a major, anonymously sourced exclusive on the investigations into the email server Hillary Clinton used as secretary of state. It is long past time for the press to stop granting anonymity to congressional sources who make uncorroborated claims smearing Clinton.

Clinton has been the front-runner for the 2016 Democratic presidential nomination for years. Congressional Republicans are so intent on preventing her from being elected that they formed a Benghazi select committee with the apparent aim of damaging her poll numbers. 

Under those circumstances, it seems impossible for a journalist to justify taking claims about Clinton from Capitol Hill sources at face value, as a Republican source's obvious motivation will be to twist the truth to cause political blowback for Clinton's campaign. To publish such a claim from a single anonymous, uncorroborated source would seem to be an exercise in journalistic malfeasance.

And yet, two of the nation's most prominent papers have made that very error over the past year, and both were forced to issue embarrassing corrections after anonymously sourced stories about Clinton's emails fell apart.

On March 27, The Washington Post published a front-page report on the FBI's investigation into Clinton's private email server that stated, “One hundred forty-seven FBI agents have been deployed to run down leads, according to a lawmaker briefed by FBI Director James B. Comey.” The Post gave no indication of why it had granted that lawmaker anonymity, whether it had attempted to confirm that number with other sources, or whether the lawmaker had actually told the reporter that the figure came from Comey.

Yesterday, the paper issued a correction, saying, “Two U.S. law enforcement officials have since told The Washington Post that figure is too high. ...  the officials say the number of FBI personnel involved is fewer than 50.”

The Post's article was roughly 5,000 words long. But reporters across the spectrum fixated on the now-retracted claim that nearly 150 FBI agents were working the email case.

In a post originally headlined “There are 147 FBI agents involved in the Hillary Clinton email investigation,” the Post's Chris Cillizza highlighted why that “eye-popping” figure was so important, reacting to the claim with surprise:

W-H-A-T?

One hundred and forty seven agents? Doesn't that seem like a ton for a story that Clinton has always insisted was really, at heart, a right-wing Republican creation?

It sure seems that way to me.

Last night, Cillizza noted the Post's correction, apologized for the error, and changed the piece's headline.

The Post has issued its correction. What will the paper's leaders do now to make sure something like this doesn't happen again?

In July, The New York Times published a front-page, anonymously sourced story on an investigation into Clinton's emails that quickly fell apart. After the paper corrected the story twice, public editor Margaret Sullivan weighed in with a blistering column calling the article a “mess” caused by “too much speed and not enough caution.” She urged the paper to undertake an analysis of “the rampant use of anonymous sources, and the need to slow down and employ what might seem an excess of caution before publishing a political blockbuster based on shadowy sources.”

Earlier this month, the Times laid out a new policy requiring “one of three top editors to review and sign off on articles that depend primarily on information from unnamed sources.” In an email to the newsroom, executive editor Dean Baquet, deputy executive editor Matt Purdy, and standards editor Philip Corbett explained:

At best, granting anonymity allows us to reveal the atrocities of terror groups, government abuses or other situations where sources may risk their lives, freedom or careers by talking to us. In sensitive areas like national security reporting, it can be unavoidable. But in other cases, readers question whether anonymity allows unnamed people to skew a story in favor of their own agenda. In rare cases, we have published information from anonymous sources without enough questions or skepticism - and it has turned out to be wrong.

Now it is the Post's turn for introspection into how it could produce such a failure.

So far, the signs are not positive. The updated version of the story now states that only “dozens” of FBI agents are assigned to the case -- but it suggests that the still-anonymous lawmaker gave the paper the correct information: “Dozens of FBI personnel have been deployed to run down leads, according to a lawmaker briefed by FBI Director James B. Comey.”

One of two things might be happening here: Either the Post is sloppily covering for its source but changing the article to suggest the source actually gave the correct information initially, or the paper went back to the source after hearing from the U.S. officials, the lawmaker changed their story, and the Post replaced the language without explaining that the source had walked back their initial claim.

Neither of those options makes the Post look good. If the Post is still protecting sources who editors know led their reporter astray, how can the paper -- or its readers -- trust that future anonymous sources will be honest?