The Daily Caller's story linking Sen. Robert Menendez to prostitutes continues to disintegrate, as questions emerge about whether the only named source in the original article was paid to make the accusations. While the focus on possible payments to the source further establishes that the story is a farce, it also risks diverting attention from the central fact that the article never should have run in the first place.

The Caller's initial story promoted the allegation that the U.S. senator had visited prostitutes. If true, as editor in chief Tucker Carlson once explained when the target of the story in question was a Republican, that allegation had the potential to bring enough media scrutiny to destroy Menendez's life. If true, it also had the potential to be a hugely important story for the Caller, one that could have undermined previous assaults on the website's credibility and established it as a true player in the Washington media.

For those reasons, one might have expected the Caller to make sure they were on solid factual footing before publishing. That's what an actual news outlet does -- reporters are constantly barraged by a wide array of claims about public figures of varying degrees of truthfulness. It's their job to examine the evidence and report out the stories that are true. Sometimes that means that responsible outlets get beaten by those that don't have such high standards for publication. But more often, this sort of scrutiny prevents the media from scurrying from one story about Barack Obama's gay affairs to another about John McCain being a Manchurian candidate -- ridiculous accusations that lack credible evidence but could serve to distract journalists and thus the public from important issues.

But the Daily Caller didn't engage in this sort of scrutiny. Instead, it appears to have channeled smears peddled by Republican operatives onto its front page without first determining their veracity.

In 2009, Carlson drew boos from the crowd at the Conservative Political Action Conference for his faint praise of mainstream news outlets, saying "The New York Times is a liberal paper, but it is also... a paper that actually cares about accuracy. Conservatives need to build institutions that mirror those institutions."

It's now apparent that if the Caller was Carlson's attempt to build such an institution, he's failed. As Joan Walsh writes in Salon, what the Caller does “mostly isn't journalism; it's opposition research.”

The Daily Caller was not alone in examining the prostitutes' tale -- it was only alone in publishing it. Reporters from ABC News, The Star Ledger, and The New York Post were all directed to the story by Republican operatives. ABC News interviewed the same Dominican women that the Caller did. But all the other outlets decided that they didn't believe the women or didn't know enough about them to proceed.

Only the Daily Caller decided that a brief Skype interview with two Dominican women its reporters had apparently never met was sufficient to accuse a U.S. senator of visiting prostitutes in the face of that senator's denial. That makes sense if you're doing opposition research to smear a political candidate. It doesn't make sense if you're trying to report out a story.

How little did the Caller know about the women whose accusations they channeled? After The Washington Post reported that Nexis de los Santos Santana, who had accused Menendez of paying her for sex, had recanted and said she was paid to lie, the Caller offered this explanation for why they believed that she hadn't been one of the women they had spoken to:

Both women TheDC interviewed said they were 24 years old at the time -- not 23 -- and neither went by Nexis de los Santos Santana. They spelled out their names and ages on camera, in the presence of Dominican lawyer Melanio Figueroa.

The Caller apparently didn't even bother to demand proof of identity from the women, who they apparently spoke to only via Skype for single, brief interviews. They simply accepted what the women had to say as true. Even the fact that they were prostitutes was apparently based on their own statements and those of Figueroa, whose credibility is now very much in question, and likely should have been all along.

Then-Caller reporter Matthew Boyle's interviews with the women do little to suggest any sort of skepticism with the story - if at some point he grilled them over details to try to ensure that they're telling the truth, that section is not included in the video posted on the Caller website. In fact, the interviews give every indication of a game plan of writing down the allegations and publishing them without regard for whether the allegations were true.

These are the tactics of opposition researchers -- bad ones, at that - not reporters.