To what extent is reporting on an unsubstantiated rumor simply spreading that rumor? There have been, recently, insinuations circulating around the internet and cable news shows alleging video footage of Michelle Obama’s use of a derogatory term about white people. As Politico’s Ben Smith—and others—have reported, there is absolutely no evidence supporting the video’s existence.

Which didn’t stop a reporter from asking Obama about it during an on-plane press conference yesterday. Obama’s response:

We have seen this before. There is dirt and lies that are circulated in e-mails and they pump them out long enough until finally you, a mainstream reporter, asks me about it. That gives legs to the story. If somebody has evidence that myself or Michelle or anybody has said something inappropriate, let them do it.

And then:

Frankly, my hope is people don’t play this game. It is a destructive aspect of our politics. Simply because something appears in an e-mail, that should lend it no more credence than if you heard it on the corner. Presumably the job of the press is to not to go around and spread scurrilous rumors like this until there is actually anything, an iota, of substance or evidence that would substantiate it.

To the extent that asking a question, when you’re a reporter for a respected mainstream news organization, tacitly legitimizes it, Obama is absolutely correct in his criticism. The reporter, in this case, represented McClatchy; the question, therefore, carries weight in the public record in ways that, had it been asked by a non-mainstream journalist, it would not. Political rumormongers rely on insufficient skepticism on the part of the press to ensure that their rumors become part of the mainstream dialogue (see “Boat, Swift”); without media complicity, those rumors’ white noise would never get filtered into the megaphone of the mainstream media. Journalists must curate as they report. Though it may, occasionally, be a fine one, there’s a line between tenacity and inanity—not just in answering questions about politics, but in asking them.

Megan Garber is an assistant editor at the Nieman Journalism Lab at Harvard University. She was formerly a CJR staff writer.