Marriage, Divorce and Sorting: A Reassessment of Unilateral Divorce Laws

I evaluate the impact of unilateral divorce laws (UDLs) on the risk of divorce via two channels: the effect on divorce of married couples (divorce effect), and the effect on marriage formation (sorting effect). The divorce effect affects the divorce probability of all married couples, while the sorting effect is only experienced by couples that married after the implementation of UDLs. I use differences in the timing of states' enactment of UDLs as a source of exogenous treatment variation in a difference-in-differences approach. Using the Divorce and Marriage file of Vital Statistics from the NBER data collection, I find that UDLs have a profound impact on marital sorting. The sorting effect significantly increases the cumulative risk of divorce within any length of marriage, while the divorce effect is only significantly associated with increasing the risk of divorce within the first 9 years and has no effect on subsequent years. Moreover, unstable marriages dissolve faster due to changes in marital sorting. The sorting effect increases the risk of divorce in each of the first 5 years of marriage by 4.5%, while there is zero divorce effect for these same years. 31% of the initial increase in the overall divorce rate identified in previous studies is due to the sorting effect.