Why do politicians lie?

The traditional public choice answer is "because they can." Once in office incumbents enjoy an electoral advantage because rational ignorance creates some slack between voter-principals and politician-agents. Politicians with enough reputational capital can afford to indulge in prevaricating rhetoric, wealth transfers to special interests, and perhaps even the occasional tryst, because democratic institutions are inefficient. Incentives matter, dammit!

The new generation of public choice invokes systematic biases in the beliefs of voter-principals deviating from political truth, as revealed by scientific method. For all the much deserved attention to Bryan Caplan's The Myth of the Rational Voter, the lesser-known yet equally forceful book, Rational Choice and Democratic Deliberation, by political theorists Guido Pincione and Fernando Teson, is well-suited to explaining systematic lies in politics and the democratic failure that results. One voter bias, due to epistemic rational ignorance, is a preference for vivid information over opaque explanations. Vivid information is

"a) emotionally interesting, b) concrete and imagery-provoking, and c) proximate in a sensory, temporal, or spatial way." For example, we will feel more indignant about a heinous crime if we watch the gory details on the evening news. If the newscaster also tells us that the suspect was out of prison on a "technicality," we will overstate the relevance of the crime as confirmatory evidence for the theory that heinous crimes are due to the leniency of the justice system. [Pincione and Teson, p.23, omitting footnotes]

In contrast, we spurn opaque explanations like invisible hand, spontaneous order, comparative advantage, reputational self-regulation, and broken window fallacies. People adopt vivid beliefs by default and confirmatory biases put a premium on vivid information that reinforces the default. So false stories can become ingrained, and [p]oliticians have an incentive to spread vivid explanations, for the public will believe them given their default views" (p.35).

Take Al Gore, who is flying to Stockholm (a shocking carbon waste!) to receive his piece of Nobel history on Monday. Yesterday's WSJ.com Opinion Journal has Holman Jenkins on "The Science of Gore's Nobel", which was "awarded for promoting belief in manmade global warming as a crisis." Jenkins invokes the same cognitive psychology that supports political failure arguments of Caplan, Pincione & Teson, and others like Tyler Cowen on voter self-deception. Voter bias finds root in anchoring effects like cognitive-cost-minimizing people choosing to adopt views that are the most available or accessible. Jenkins:

[Kahneman and Tversky's] insight has been fruitful and multiplied: "Availability cascade" has been coined for the way a proposition can become irresistible simply by the media repeating it; "informational cascades" for the tendency to replace our beliefs with the crowd's beliefs; and "reputational cascade" for the rational incentive to do so.

Mr. Gore clearly understands the game he's playing, judging by his resort to such nondispositive arguments as: "The people who dispute the international consensus on global warming are in the same category now with the people who think the moon landing was staged in a movie lot in Arizona."

Here's exactly the problem that availability cascades pose: What if the heads being counted to certify an alleged "consensus" arrived at their positions by counting heads?

Falsely claiming consensus behind one's views is a form of political deception, which as Pincione and Teson point out, commits the argumentum ad populum fallacy. Logic be damned. Rather, "citing agreement of others is, in short, a particularly vivid (and often fallacious) way to argue in politics." (p.43)

What this all amounts to is a refinement of government failure theory. Throw cognitive biases together in large numbers and systemic failures pop out. Pincione and Teson:

Discourse failure as a social phenomenon results...from the mutually reinforcing interaction of rational ignorance and posturing against the background of redistributive politics. Political actors who stand to gain from spreading certain kinds of information will be helped by citizens who are willing to do their share, as it were, in the acquisition of confirmatory evidence of the default vivid beliefs. In other words, the cost of supplying convenient information is reduced by ingrained cognitive errors, and correspondingly, those who want to change public opinion in the direction of opaque theories will face higher costs. Not only will they have to argue against vivid views that the public holds by default; they will also have to counter the psychological biases just discussed. (p.44)

Politicians lie because they can, yes, but also "because they have to!" Incentives yada yada. Perceptions matter too, dammit!

Hat tips to:
Nico Maloberti for showing me the Pincione and Teson book;
Richard Reinsch for pointer to the Jenkins WSJ.com article.

Here is Jenkins on the science of global warming: "Let's be honets, all we have is a hypothesis."
Here is my previous entry on the challenges of Liberal persuasion.