We study the effect of a 2006 reform to Italian family law that made joint custody the default for separating couples. The reform boosted joint legal custody by about 75 percentage points. Our research design uses difference‐in‐differences to estimate reform effects on the likelihood of a contested settlement, length of trial, and transfers between separating parents. The analysis is based on Italian individual‐level administrative data, which cover the entire population. The joint custody default appears to have increased dispute rates and length of trial markedly, without affecting transfers. There is no evidence that mothers buy custody rights back through reduced support. Our findings are consistent with the excessive discretion given to judges on some aspects of law implementation, which resulted in a partial application of the reform.

中文翻译：

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意大利共同监护法的效力

我们研究了2006年对意大利家庭法进行的改革的影响，该改革将共同监护权作为夫妻分居的默认设置。改革使联合法律监护权提高了约75个百分点。我们的研究设计使用差异来估计改革对有争议的和解可能性，审判时间以及父母分离之间的转移的影响。该分析基于覆盖整个人口的意大利个人级别的管理数据。联合监护的默认情况似乎显着增加了争议率和审判时间，而不会影响移送。没有证据表明母亲通过减少支持来回购监护权。我们的发现与在法律实施的某些方面给予法官过多的酌处权是一致的，这导致了部分改革的实施。