Our chapter on the mass media discusses the extent to which reporters rely on opposition researchers. At National Review Online, former senator and presidential candidate Fred Thompson writes of their possible role in the Cain allegations:
Initially, Cain lashed out at the liberal media. So did several conservative commentators. But I doubt that Politico, which published the story first, came up with this scoop by investigating Cain’s background on its own.
People may think that news organizations have legions of Woodwards and Bernsteins fanned out across the country, poring through old courthouse records or public business records and talking to anyone they think may have some dirt to dish on a candidate. They don’t. They don’t have the money, for one thing. No, the days of Woodward and Bernstein, intrepid investigative reporters, are over. Investigative reporters have been replaced by people who keep a big basket under the transom to catch the dossiers and other materials that the various campaigns drop on opposing candidates.
Campaigns that can afford it often spend lots of money on “opposition research.” The research can be for perfectly legitimate things, such as positions candidates have taken on issues. Or it can be for personal dirt, substantiated or otherwise. If they pass it to the media, the campaign, of course, wants to keep its role secret. In this way, reporters are seldom investigators. More often they’re facilitators. It’s easier work.
Thompson goes on to explain why he thinks the story came from a GOP source. He recalls how he sustained "oppo" attacks during his unsuccessful bid for the 2008 Republican nomination.
Also at National Review Online, Andrew C. McCarthy writes:
Politico has now framed discovery of the identity of the source as is a noteworthy story. Yet, Politico knows that if the identity of the source is a story, it is only because Politico itself is being coy. Politico has reported that Perry may be the source and that Romney may be the source. Yet, Politico knows precisely whether the Perry campaign or the Romney campaign (or both . . . or neither) is the source. It is thus almost certainly true that at least some of the conflicting allegations Politico is airing are known by Politico to be false. In fact, both the Perry and Romney camps have denied involvement — if it so happens that one of those camps is the source, then Politico knows the denial is a lie, yet it published the denial anyway. That would amount to colluding with its source in order to tarnish Cain while fraudulently portraying its source as above the fray.
In sum, Politico is publishing at least some things it knows to be misleading or untrue, and framing as a great mystery something to which it knows the answer. That can only be because Politico finds the specter of the Republican circular firing squad more appealing than the prospect of informing readers of the accurate version of events.