Applying the Coase Theorem to marital bargaining suggests that shifting from consent to unilateral divorce laws will not affect divorce rates. I show that existing evidence suggesting large effects of divorce laws on divorce rates reflect a failure to explicitly model the dynamic response of divorce rates to a shock to the legal regime. When accounting for these dynamics, I find that unilateral divorce spiked following the adoption of unilateral divorce laws, but that this rise largely reversed itself within a decade. Overall, these changes in family law explain very little of the rise in divorce over the past half-century.
Justin Wolfers (2006) studied this question.