Diehard supporters of Sen. Bernie Sanders (I–Vt.) have long believed that the mainstream media finds subtle ways to undermine their candidate—and occasionally their suspicions are well supported. Tuesday night's Democratic debate provided another one of these moments, as the progressive believe-all-victims mantra led CNN's Abby Phillip to presume the truth of the unproven accusation that Sanders privately told Sen. Elizabeth Warren (D–Mass.) that a woman couldn't win the presidency.

The accusation surfaced over the weekend, with the media citing unnamed sources—likely members of the Warren campaign—who claimed that Sanders made the comment during a meeting with Warren in 2018. Sanders vehemently denied saying this, and was asked about it again on the debate stage.

It was a fascinating exchange. When Sanders again stated that the story wasn't true, Phillip asked, "You're saying that you never told Senator Warren that a woman couldn't win the election?"

"Correct," Sanders responded.

Phillip then turned to Warren and asked, "Senator Warren, what did you think when Sen. Sanders said a woman couldn't win the election?"

CNN: "You're saying that you never told Senator Warren that a woman couldn't win the election?" Bernie: "Correct." CNN: "Warren, what did you think when Sanders said a woman couldn't win the election?" Reminder: CNN helped rig the primary against Bernie in 2016. #DemDebate pic.twitter.com/xMxwI3Mq8h — Alex Marlow (@AlexMarlow) January 15, 2020

Note that Phillip did not actually ask Warren whether he had made the comment—she merely presumed that he had, even though he just denied it. Moments later, CNN.com ran with the headline, "Sanders denies saying a woman can't be president." This framing of the subject makes it sound like Sanders is denying some objective reality—even though there's no evidence he said it, and Warren's recollection of the statement was not specifically probed by the moderator.

CNN missed an important opportunity to shed some light on a rare dispute between Sanders and Warren. Instead, they punted—in a manner that implicitly took Warren's side. No doubt many of Sanders' most fervent online backers found that telling.