The case for Hillary Clinton's proposal to make voter registration automatic is simple: it will make it easier for people to vote.

The case against Hillary Clinton's proposal to make voter registration automatic is also simple: it will make it easier for people to vote.

If that sounds a bit odd to you, then read Daniel Foster's argument against Clinton's idea, which lays the objection bare: "the people who can’t be bothered to register (as opposed to those who refuse to vote as a means of protest) are, except in unusual cases, civic idiots." And who wants civic idiots choosing our next president?

@zackroth yes. The point is that "moar democracy" isn’t automatically superior, if the new voters you’re bringing in are less informed. — Daniel Foster (@DanFosterType) June 5, 2015

For a rejoinder, read Slate's Jamelle Bouie, who writes, "You get better at voting the more often you do it. Relatively uninformed voters in one election might become highly informed voters a few cycles later. More participation could make us a more engaged country."

Lurking in both arguments is this idea of the informed voter — the voter who can tell you that conservatives hold a slim majority on the Supreme Court, who knows that the House majority whip is an important position, who reads about politics and donates to campaigns and knows exactly where her polling place is.

That voter commands more facts, for sure. But is that voter truly more informed? Maybe not.

More information doesn't always mean better conclusions

In 2006, the political scientists Christopher Achens and Larry Bartels presented a paper titled "It Feels Like We're Thinking: The Rationalizing Voter and Electoral Democracy." In it, Achens and Bartels make a point that is so obvious we often forget its implications: "Very few politically consequential facts are subject to direct, personal verification."

In other words, an informed voter rarely knows anything firsthand, the way we know the sky is blue and the sun rose this morning. Everything she knows is taken on trust; an informed voter is only as good as her information sources. And because we all get to choose which information sources to believe, voters with more information are not always more informed. Sometimes, they're just more completely and profoundly misled.

Looking at the 1996 election, for instance, Achens and Bartels studied whether voters knew the budget deficit had dropped during President Clinton's first term (it had, and sharply). What they found will shake anyone who believes more information leads to a smarter electorate: how much voters knew about politics mattered less than which party they supported. Republicans in the 80th percentile of political knowledge were less likely to answer the question correctly than Democrats in the 20th percentile of political knowledge.

It gets worse: Republicans in the 60th percentile of political knowledge were less likely to answer the question correctly than Republicans in the 10th percentile of political knowledge — which suggests that at least some of what we learn as we become more politically informed is how to mask our partisanship by spouting things that sound that like facts, but often aren't:

Similar experiments have shown similar self-deception among Democrats when the questions favor Republican ideas or politicians. Achens and Bartels's conclusion is grim: much of what looks like learning in American politics is actually, they argue, an elaborate performance of justifying the beliefs we already hold. "Most of the time, the voters are merely reaffirming their partisan and group identities at the polls. They do not reason very much or very often. What they do is rationalize."

Voters choose experts who agree with them

To see how this works, it's worth looking at an experiment conducted by Yale Law professor Dan Kahan. In it, Kahan and his colleagues showed 1,500 people sample biographies of highly accomplished scientists alongside a summaries of their research. Then they asked whether the scientist was indeed an expert.

It turned out that people’s actual definition of "expert" is "a credentialed person who agrees with me."

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For instance, when the researchers' results underscored the dangers of climate change, people who tended to worry about climate change were 72 percentage points more likely to agree that the researcher was a bona fide expert.

But then Kahan took the same researcher with the same credentials and flipped the summary of his results. All of a sudden, people who tended to dismiss climate change were 54 percentage points more likely to see the researcher as an expert. People's perception of expertise, at least on controversial political issues, flows backward from their conclusions — they're looking for authorities who ratify what they already believe, not someone who will help them figure out what to believe. (It's not just climate change, by the way: a similar gap was evident when subjects were asked to judge experts on gun control.)

In a world where we pick our information and our experts based on whether we agree with them, it's little surprise that sometimes the most informed can be the most badly misled. For instance, 9/11 truthers typically have a tremendous amount of information about 9/11 at their disposal. They know much more than the average American does about the physical composition of the Twin Towers, and the melting point of steel, and the pattern of warnings that preceded the attacks. But they have used that information to convince themselves of something that isn't true.

Elections select for partisanship, not information

The same process can play out, in less dramatic fashion, with hardcore partisans. In 2003, I knew a lot of very informed liberals who were skeptical that President George W. Bush would even allow a presidential election — at the time, many lefties feared the establishment of martial law, or at least the wholesale theft of the election through the use of Diebold voting machines. In 2010, I knew many very informed conservatives who believed Barack Obama was secretly a Muslim born in Kenya, and therefore ineligible to hold the presidency.

If you ranked these groups in terms of political knowledge, they would be off the charts. They were constantly reading about politics online, learning about the issues, talking to other high-information partisans. But their information, as voluminous as it was, had profoundly misled them. They had a much less accurate view of American politics than people who paid far less attention to the news.

Hurdles to voting don't primarily select for intelligence; they select for interest in American politics. That's why Pew finds that people are most likely to vote when they're consistently conservative or consistently liberal. Those are the people most ferociously committed to winning the ongoing war that is American politics — and for that reason, those are the people who see the most reason to go to the polls, and those are the people the two parties make the largest effort to push to the polls.

But a ferocious commitment to destroying the other side in American politics doesn't necessarily lead to clear reasoning on the issues facing the country. Partisanship is normal and even healthy in a competitive democracy, but it's not such an unalloyed good that we should be biasing the electorate toward hardcore partisans.

Universal voter registration won't necessarily mean that dumber Americans heads to the polls; it will mean that less politically attached Americans head to the polls. And in an age as polarized as this one, that's probably a good thing.

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