I’m not sure why Ezra Klein thinks it’s especially significant that studies don’t find obvious academic benefits accruing from D.C.’s voucher program in its first year of operation. Yes, the greater flexibility enjoyed by private actors is one part of the argument for choice, but the real core of the argument is about the market process, not about anything inherently magical about private status. Actually, coming from a status quo in which public school is free and tends to vary in quality with neighborhood property values, I’d expect many preexisting private schools, especially the religious ones, to have been selected for fulfilling the specific goals of parents reluctant to place their kids in a secular system, not for special academic excellence.
Rather, the idea is supposed to be that, while there will be a mix of good and bad schools to start, over time price signals and market pressure will spur the formation of new schools to meet demand, force existing ones to adapt in whatever way attracts parents, and eventually eliminate the ones that fail to deliver the goods. Maybe there are overheated voucher boosters out there promising instant improvements, but there’s relatively little reason to expect a market for education to show its advantages right out of the starting gate. If a broad, well-designed, and generous voucher program shows no advantages a decade in, then obviously that’s more telling—though ceteris paribus I’d think there’s some independent, intrinsic value to parental choice. In any event, I don’t think you get to pat yourself on the back for your rigorous empiricism if you cry “Nothing to see here” after a year of vouchers, then return to insisting that urban public schools that’ve been wretched for a generation will finally turn around, if only we Care Bear–stare hard enough.