Helen Ladd has followed her poignant charter school segregation study with a new one on the financial impacts of charters on the public school system.  Two years ago, she, Charles Clotfelter, and John Holbein released Growing Segmentation of the Charter School Sector in North Carolina.  They found that the state's charter schools were becoming increasingly white, while its charters were becoming increasing populated by students of color.  It was probably the most precise and impactful study on the topic of charter school segregation to date. 

I separately theorized that this particular demographic trend was occurring in North Carolina as a response to relatively high levels of integration in the public schools.  In other states, the typical charge is that charters are predominantly minority and more segregated than the traditional public schools.  While far from perfect, North Carolina's traditional public schools have tended to be some of the most integrated in the nation.  This is partly attributable to the fact that there are 100 counties in the state and only 102 or 103 school districts.  So those who object to integration cannot simply flee to a suburban district--at least not easily.

Charters schools potentially change that in North Carolina.  The so-to-speak dissenters can simply enroll in a local charter now.  This is not to say that all North Carolina charters play this role, but Ladd's work suggests that many do.

Her new study suggests that not only are these charters segregating education, they are draining funds from the regular public schools.  Her abstract states:

A significant criticism of the charter school movement is that funding for charter schools diverts money away from traditional public schools. As shown in prior work by Bifulco and Reback (2014) for two urban districts in New York, the magnitude of such adverse fiscal externalities depends in part on the nature of state and local funding policies. In this paper, we build on their approach to examine the fiscal effects of charter schools on both urban and non-urban school districts in North Carolina. We base our analysis on detailed balance sheet information for a sample of school districts that experienced significant charter entry since the statewide cap on charters was raised in 2011. This detailed budgetary information permits us to estimate a range of fiscal impacts using a variety of different assumptions. We find a large and negative fiscal impact from $500-$700 per pupil in our one urban school district and somewhat smaller, but still significant, fiscal externalities on the non-urban districts in our sample.

This study only adds fuel to theory I offer in Preferencing Choice: The Constitutional Limits.