The HuffPo provided a similar update at the top of its report: “CORRECTION: An item posted here — reporting that Supreme Court Justice Antonin Scalia said that if he were on the court in 1954, he would have dissented in the landmark Brown vs. Board of Education decision that ended school segregation based on race — was incorrect.” The HuffPo piece has helpfully maintained the text of “our original, incorrect report”; at the same time, in tacit recognition of the fact that many of its readers are more accurately ‘headline skimmers,’ it has changed its headline to reflect the error of the original post: “Scalia Misquoted on Brown v. Board of Education (CORRECTED).”

Meanwhile…the newspaper—the originator of the flawed reporting, and the only member, in this crowd, of that increasingly nebulous group known as the MSM—initially simply scrubbed the offending passage from its Scalia story, without a note of explanation. Then, late in the day yesterday, it replaced the initial story with a new one. “Capitol Media Services sent an updated and corrected version of the story, which we have posted,” East Valley Tribune editor Chris Coppola told me in an e-mail yesterday evening. “It also notes the correction.”

The story now begins with an editor’s note referencing the initial ‘Scalia would dissent from Brown’ claim: “This is an updated version of a story that was originally posted Oct. 26. It removes an incorrect reference to Brown v. Board of Education in the initial version.” But the only records of the story’s original claims, on the story’s page on the Tribune sites, are phantom references to them in the article’s comments section. If one wanted to find the original claims…one would have to go to the HuffPo piece.

All of which has, to step back from Scalia for a moment, a full-circle quality to it: the bloggers exhibiting responsibility to their audience, the students becoming the masters, the circle of life, etc. In the teeming world of the Web—one defined not merely by seemingly endless variety on the part of news outlets, but also by, consequently, seemingly endless choice on the part of news consumers—one of the rarest and therefore most valuable commodities is trust.

That tenuous good—a function of authority, accuracy, and audience attention—is a limited resource largely because one of its key components—attention—is itself finite. Each audience member has only a limited amount of attention he or she can give to news stories. And that limited resource, in turn, leads to a tension between plenty—the variety and redundancy of news outlets available to audiences—and scarcity. With the end result being, among other things, that no longer is reader loyalty something that can be safely assumed, in the old ‘well, where else are they going to go for their news?’ model. In our world of media plenty, no longer is the cultivation of trust one component of the journalistic equation; it is a key component. It is, in many ways, the component: If people doubt the accuracy of the journalism you produce—or, worse, if they don’t pay attention to it in the first place—then what, really, is the point?

For bloggers, whose journalism evolved with the Web, the visceral instinct toward trust—the implicit recognition of its primacy—is coded, so to speak, into their journalistic DNA. Mainstream outlets, on the other hand—outlets which, up to now, have been able to take their readership largely for granted—don’t generally share that instinct. They’ve always been interested in cultivating trust, of course—trust builds audiences, which builds both revenue and journalistic impact—but their relationship with trust has been more detached. They’ve generally understood trust as something to be ‘earned’…but not as something that is implicitly, and existentially, necessary. While they’ve had to work to maintain reader trust…they haven’t had to work too hard at it. Because, again: where else are the readers going to go?

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