Back in 2006, California voters decisively rejected liberal Hollywood director/activist Rob Reiner’s ballot initiative that would have provided government preschool to all four-year-olds. Yet, like a bad penny, efforts to resurrect universal government preschool keep turning up.

California’s newly elected governor Gavin Newsom campaigned on a promise to expand dramatically government preschool programs to younger children. He outlined his “California Promise” stating: “Our role begins when babies are still in the womb and it doesn’t end until we’ve done all we can to prepare them for a quality job and successful career.”

In December, Democrat California Assemblyman Kevin McCarty introduced several preschool-related bills, including one that would provide “high-quality universal preschool” through a combination of various programs “to all four-year-old children.”

California isn’t the only place pushing universal preschool.

In Chicago, Mayor Rahm Emanuel has rolled out a $175 million plan to offer government preschool to all four-year-olds by 2021-22. Interestingly, universal preschool proponents often cite the results of an earlier preschool program, the Chicago Child-Parent Center program for low-income children, to bolster their case for universal preschool. However, looks are deceiving.

It turns out that the Chicago Child-Parent Center program relied on extensive parent training, a feature notably absent from universal preschool proposals such as Assemblyman McCarty’s in California.

As psychologist Dr. Michael Thompson of Children’s Hospital in New Orleans noted, if policymakers mistakenly believe that preschool results in better life outcomes, “they may mistakenly invest in these programs when the money might be better invested in parenting-skill programs or other interventions to increase parental involvement.”

Overall, data do not support the call for increased taxpayer investment in government preschool.

Proponents claim that getting more young children into universal preschool programs will boost school performance and close alleged achievement gaps.

However, Vanderbilt University professors Dale Farran and Mark Lipsey, writing for the Brookings Institution, warn that the most-cited studies used to advocate for universal preschool are inadequate for claiming any long-term benefits of pre-K programs since the programs studied were so small and targeted.

“Contemporary preschool programs are not like these intensive small-scale demonstration programs,” say Farran and Lipsey.

“To assert,” say the Vanderbilt professors, “that these same outcomes can be achieved at a scale by pre-K programs that cost less and don’t look the same is unsupported by any available evidence.”

In fact, Farran and Lipsey point out that more in-depth studies of the lasting impact of public preschool programs, including the federal Head Start program for low-income children and Tennessee’s Voluntary Pre-K program, reveal that “early gains at the end of pre-K were not sustained as long as to the end of kindergarten.”

By second and third grade, the academic performance of children in the Tennessee pre-K program lagged the control group of children who did not participate in the program.

By third grade, the children in the Head Start program were found to be more aggressive and have more emotional issues than the children who did not attend the program.

Further, there is little evidence that universal preschool programs have lasting benefits for non-disadvantaged children.

Looking at available research at the time of Rob Reiner’s universal preschool initiative, RAND found that “children participating in preschools not targeted to disadvantaged children were no better off in terms of high school or college completion, earnings, or criminal justice system involvement than those not going to preschool.”

We all want to help children succeed and flourish. The messaging that surrounds expansion of universal preschool programs glowingly suggests that earlier schooling will close achievement gaps, improve academic performance and emotional health, and have an enduring, positive impact on a child’s life and livelihood.

Much evidence, however, suggests otherwise. Taxpayers should be wary of supporting pre-K expansion plans that may sound promising but fail to deliver desired results.

Lance Izumi is senior director of the Center for Education at the Pacific Research Institute, a nonprofit group that advocates for limited government. Kerry McDonald is an education policy writer and author of the forthcoming book, Unschooled: Raising Curious, Well-Educated Children Outside the Conventional Classroom.

The views and opinions expressed in this commentary are those of the author and do not reflect the official position of The Daily Caller.