Despite a tenuous yet neat metaphor running through the spine of Merchants of Doubt, this eviscerating documentary about the meeting of science and politics is potent and cleverly crafted.

Attacking those who fight, obfuscate, circumvent, and simply derail science and research meant to inform the public, Merchants of Doubt details the systematic way in which basically things in Washington D.C. come to a halt.

There are some in the business of being meddlesome and obstructionist, casting doubt on say, the validity of climate change data or the dangers of cigarettes. Running as basically a lengthy Daily Show (well, now Late Night) editorial, the films begins with a magician offering his thoughts on sleight of hand, misdirection, and the games at which people will never win, despite being oh so sure they will.

It’s a loose analogy, but as director Robert Kenner (Food, Inc.) unearths in talking to scientists, historians, and some very smug and oblivious ‘merchants,’ these businessmen tend to best rational, scientific, and apolitical endeavors.

Merchants is a funny film in that those it effectively and deservedly tears down are laughably ridiculous, but it’s has a powerfully frustrating element too. There is also a tragic side, because perhaps we’re not really that surprised. Basically scientists write science, and then are forced to defend themselves against PR goons.

Kenner’s doc triumphs when it uncovers the motivations behind these merchants and discloses their lies and deceits. If nothing else, it’s a firm reminder to question everything – especially those questioning you.

[star v=4]