By Dan Lips

Anytime a liberal politician says something positive about school vouchers, it's notable.  When that politician is a leading contender for the Democratic presidential nomination, it merits national attention. 

In a recent meeting with the editorial board of the Milwaukee Journal Sentinel, Illinois Senator Barrack Obama made headlines by indicating that he could possibly support school vouchers.

The newspaper reported that, while claiming to be a skeptic, Sen. Obama promised he would keep an open mind: "If there was any argument for vouchers, it was 'Let's see if the experiment works,'" Senator Obama said. "And if it does, whatever my preconception, you do what's best for kids." 

Academic studies showing that vouchers are working might convince Senator Obama to become a supporter, or so the Journal Sentinel reported. 

The Illinois Senator deserves credit for keeping an open mind about a controversial reform idea that is opposed by most liberal interest groups. But apparently he is not up-to-date on the latest education policy research. If he or his staffers had been doing their homework, they would know that many academic evaluations have already shown that voucher programs are working.

One such program is in Milwaukee. Originally launched in 1990, it is now helping more than 17,600 low-income students attend private schools, and its success has been documented by a growing body of academic research. 

The Milwaukee voucher program has undergone two randomized-experiment evaluations. Considered the gold standard in scientific research, these experiments compare a group of students who were awarded vouchers through a lottery system with students who applied but did not get vouchers. This allows researchers to test the "treated group" with their peers who stayed in public schools. Both academic evaluations have shown academic gains over time for students receiving vouchers.

School choice also leads to higher graduation rates. Students in the Milwaukee voucher program have higher graduation rates than students in traditional public schools. Dr. John Robert Warren of the University of Minnesota compared the graduation rates of voucher recipients to students the city's public school system. He found that in three out of four recent years, the graduation rate for voucher students was significantly higher. "Overall, had MPS graduation rates equaled those for MPCP students, the number of MPS graduates would have been 14 per cent higher in these four years," Dr. Warren concluded. 

Furthermore, the benefits of school choice aren't confined to students receiving vouchers. Growing evidence suggests that public schools are spurred to do better when families have the option of choosing different schools for their kids. In 2001, Harvard University Economics Professor Dr. Caroline Hoxby studied the effect of school choice options on the performance of public schools. She found that public schools that faced a higher degree of competition from private schools improved their performance compared to public schools that faced less competition. A new evaluation conducted by Federal Reserve Bank economist Rajashri Chakrabarti has also found that competition has led to improvement in Milwaukee public schools.

In the future, experts will know even more about how well school choice programs are working.  The Wisconsin state legislature recently ordered that academic researchers conduct a longitudinal study of the Milwaukee voucher program to determine how well it is working. Georgetown University researchers are currently conducting a similar evaluation of the school voucher program in Washington, D.C. 

But Senator Obama doesn't need to rely on academic research alone.  Parents are the best jury to decide whether choice is working for their children. On that point, the evidence is strong. Many surveys and focus groups have found that parents are more satisfied with their children's learning environment when they can choose their school. That helps to explain why limited voucher programs are usually over-subscribed, with many kids ending up on long waiting lists. 

What's more, Senator Obama should ask the millions of low-income families who have no choice but to send their kids to low-performing public schools if they too would like a voucher.  In 1998, the non-profit Children's Scholarship Fund did just that - offering private school scholarships to 40,000 low-income students across the country. In all, more than 1.2 million kids applied. In Senator Obama's hometown of Chicago, 59,000 children applied - approximately one out of every four kids who was eligible. 

It's a welcome sign that a Democratic presidential candidate is keeping an open mind about school choice. But he need not wait for the next round of academic research reports to understand that school choice works. The evidence is already clear. 

Dan Lips is Education Analyst at the Heritage Foundation.