A new paper published by the National Bureau of Economic Research found that California’s 2004 paid leave law, which provides an extra six weeks of paid leave at 55% of one’s pay, didn’t do what it was supposed to do: get mothers back to work.

“The authors find scant evidence that the policy increased employment,” writes Robert VerBruggen at the Institute for Family Studies. “Further, while many hoped that paid leave would help mothers stay with their current employers instead of finding new jobs when they returned to the workforce, this behavior didn’t increase, either. Some mothers apparently transitioned to more flexible work arrangements or cut back their hours.”