The common element in nearly all the major New York Times and Washington Post stories about President Donald Trump this week is that they are based on source documents the outlets cannot authenticate, do not possess, admit are partial, and refuse to share.

Friday’s supposed “bombshell” stories follow the same pattern. The Times reports that Trump told the visiting Russians that former FBI director James Comey was a “nut job,” and that firing him had eased “pressure” in his ability to conduct foreign policy — though the Times takes Trump to mean the legal pressure of the investigation. (That spin makes no sense: firing Comey created more pressure, which was so obvious the Russians joked about it.)

The Times describes its source as “a document summarizing the meeting” that was “circulated” (it does not say by whom). The Times does not have the document. An “American official” simply “read quotations” to the Times.

The Post‘s story, which reports that the probe into potential ties between Russia and the Trump campaign has reached “someone close to the president,” cites “people familiar with the matter.” That does not prove the story is untrue, but the sources are so flimsy that there is no way to have confidence in what the Post calls its “revelation.”

Earlier this week, the Post reported that House Majority Leader Kevin McCarthy (R-CA) told a meeting of fellow House Republican leaders: “I think Putin pays [Trump].” According to those present, the remark was a joke. The Post‘s source was an audio recording of the conversation which it did not have in its actual possession, and which it refuses to share with the public so that people can judge for themselves. The Post did publish a transcript, which it does not appear to have produced itself. The transcript actually supports the claim that McCarthy was joking. The Post‘s reporter has insisted that McCarthy meant his remark to be taken seriously, but refuses to provide the audio.

And the day before that, the Times published the now-infamous story that Trump had “asked” Comey to end the investigation into former National Security Adviser Michael Flynn. The source was purportedly a memorandum that Comey wrote about his recollection of a conversation with Trump. But the Times did not share the memo, and never even saw the document. It merely relied on a Comey “associate” who “read parts of it to a Times reporter.”

These four stories, taken together, are said by the mainstream media to build a powerful case that Trump committed obstruction of justice and may soon face impeachment. But every piece of evidence could be made up or distorted, and there would be no way to know. In the “nut job” case, the White House has not disputed that Trump made the comment, but it may not be able to explain the context, because doing so would mean releasing more details of a classified conversation that touched on “highly classified” national security matters (as the Post reported on Monday.)

In their effort to impugn Trump, the Times and the Post violate the most basic journalistic standards. Publishing parts of a document that you do not possess and cannot verify, and timing the release to cause maximum political damage (right after the president leaves the country), is not investigative journalism. It is political propaganda.

It is the mirror image of what the Los Angeles Times did in April 2008, when it published a story referring to a speech then-State Senator Barack Obama gave at a farewell celebration for radical Palestinian-American academic Rashid Khalidi in 2003. The Times was given a video of the speech, but refused to publish the video. Instead, it offered a mere summary, raising suspicions that the Times had sanitized the event to protect Obama’s presidential campaign.

The pattern is the same, from the Khalidi tape to the “nut job” story. For the elite mainstream media, when it comes to protecting Democrats or attacking Republicans, there are no journalistic standards, no ethics, and no shame.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He was named one of the “most influential” people in news media in 2016. He is the co-author of How Trump Won: The Inside Story of a Revolution, is available from Regnery. Follow him on Twitter at @joelpollak.