Speaking of organizations gaining credibility through conversation: On Monday, the investigative nonprofit ProPublica wrote a story on how Goldman Sachs apparently pushed some of its clients to bet against some California bonds, even though the state had paid Goldman to help sell them. I don’t pretend to understand the ways of high finance, but it seemed like a good story to me. I happened to be in a room with ProPublica chief Paul Steiger the day it came out, and he seemed happy with the story.

But on Tuesday, Portfolio business writer Felix Salmon — another smart guy — came out with a piece calling the ProPublica scoop a “hatchet job,” arguing that what Goldman did is perfectly normal — that as a bank, it had separate responsibilities to those for whom it issues debt and for those it helps invest. Salmon lays out a case that seems, at least to these eyes, to have some merit.

Who’s right? One smart guy against a news organization filled with smart people. Heck if I know. But there’s one mistake I do think ProPublica is guilty of.

Salmon talked to ProPublica’s Dick Tofel about the story:

I just got off the phone with ProPublica’s Dick Tofel; we talked quite a bit about the Goldman Sachs story they put out yesterday, but unfortunately they don’t seem inclined to say anything on the record. [Emphasis mine.]

I know this has been the traditional route of news organizations — to say “the story speaks for itself, and we stand by it.” And I can understand why an organization doesn’t want to respond to every random crank. And obviously, journalists need to protect their sources.

But Felix Salmon isn’t some random crank. He appears to raise legitimate objections to a major story, and there’s no apparent reason why ProPublica would need to protect a source to answer them. When that happens, the audience deserves to understand why ProPublica believes they’re right and Salmon is wrong. It isn’t enough just to mollify Salmon (which Tofel’s conversation didn’t appear to); the readers deserve an honest exchange of evidence and ideas.

The UC Berkeley economist Brad DeLong — who, in fairness, is not predisposed to great admiration of the press — put it this way:

A word to ProPublica: in the age of the internet, answering questions about your stories is part of the job. Clamming up — saying that you will not answer questions about why you wrote the stories you did unless you can take it off the record — is the quickest way to burn credibility I can think of.

One footnote: As I type this, five of the top six search results for “propublica goldman sachs” on Google are links to critics of the article. The article itself comes in only at No. 4. Another reason why the conversation around a story can be as important as the story itself — Google loves links.