Speaking in Iowa yesterday, Rick Perry warned an audience of conservatives not to believe the recent good jobs news, claiming that the unemployment rate has “been massaged, it’s been doctored.” As far as I can tell, this is a conspiracy theory of relatively recent vintage: It goes back to the weeks before the 2012 election, when former GE CEO Jack Welch declared that a modest, unexpected drop in the unemployment rate was “unbelievable” and could be explained only by “Chicago guys” cooking the books to re-elect President Obama. As former Labor Department officials politely pointed out, this was a loony, completely uninformed assertion—since any conspiracy to manipulate the official jobs statistics would involve huge numbers of people and be nearly impossible to pull off.

It would be easy to see Welch’s claim, and its eager reception in conservative circles, as the sort of campaign noise which quickly subsides after the election has ended. (Rick Perry’s silly invocation of the conspiracy theory in Iowa supports this interpretation.) But it’s actually part of a much more serious, widespread effort to undermine institutions and figures whose authority depends precisely on their credibility—and who are among the few agreed-upon sources of appeal left in political debate. Launching spurious accusations against respected, disinterested organizations is one of the most worrying games the right plays.

To be clear, the risk here is not that we owe some blanket deference to expert or governmental authority, and that conservative attacks will undermine that proper deference. Experts can be wrong; governments lie. But there are standards that separate skepticism from paranoia and accusations from wild speculation. The Bureau of Labor Statistics (unlike, for example, the CIA) has no record of misleading the public; its statistics (unlike, for example, Chinese economic statistics) enjoy credibility among scholars, foreign governments, and businesspeople; and nobody familiar with its data collection methods thinks manipulation would really be possible. In other words: It’s a terrible candidate for a conspiracy theory.

But none of that matters, because smearing the BLS was never the result of a well-intentioned skepticism that simply happened to go overboard or miss its target. The aim, all along, has been to tarnish authoritative sources of empirical knowledge, wherever they conflict with the conservative agenda. It’s no accident that the right delights in convenient attacks on the BLS, climate scientists, the “liberal media,” or major universities. Official government agencies, scientists and other scholars, and journalists are crucial sources of public knowledge, and whatever authority they have comes from their reputation for professionalism and integrity.

Proof of this disturbing intent came in another news story from just before the 2012 election—albeit one that received far less attention. It was the decision by the Congressional Research Service to bend to the complaints of Senate Republicans and withdraw a report casting doubt on the relationship between top tax rates and economic growth. The Congressional Research Service (CRS), like the BLS, produces authoritative information on important topics, and like the BLS, there are no credible accusations that it’s either corrupt or biased.

In the case of the CRS report, the move was simple: Raise such a protest that the agency would crack under political pressure. BLS jobs numbers can’t be suppressed in the same way, but they can be attacked and undermined—bringing us ever closer to a public sphere where policy arguments are almost entirely dissociated from fact. In the mid-2000s, the line was: Don’t listen when people claim that Iraq has descended into civil war, because you can’t trust the liberal media. Or: Don’t believe in the climate change hoax, because you can’t trust left-wing scientists. Today, it’s: Don’t buy the jobs numbers, because you can’t trust the BLS. None of this is to deny that a well-tempered skepticism is the best defense against the kind of dull-minded complacency that makes people easy targets for manipulation. But politically motivated paranoia driven by venal politicians and Fox News agitprop is not skepticism on steroids—rather, it’s a certain route into the very same manipulation that skepticism is supposed to prevent.