On the CNN debate stage Tuesday night, Bernie Sanders flat-out denied that he ever told Elizabeth Warren that a woman couldn’t be president, a hard-to-believe rumor reported this week.

But the debate moderator next asked Warren to respond to Sanders’s statement that a woman can’t win — essentially, accepting the premise of the rumor as if it were established fact. Warren responded, “I disagree,” implying, without any evidence and despite the denial, that he did ask it and saying, “This question has been raised, and it’s time for us to attack it.”