Can child marriage law change attitudes and behaviour? Experimental evidence from an information intervention in Bangladesh

The practice of child marriage is ubiquitous in developing countries, where one in three girls is married before the age of 18. Although most developing countries have a legal minimum age of marriage, in practice marriage age is determined by social norms rather than the law. In this paper, we test the hypothesis that formal laws can influence social norms and marriage behaviour in a setting with weak law enforcement. We do this by administering a randomised video-based information treatment that accelerates knowledge transmission about a new child marriage law in Bangladesh. Our information treatments led to a change in participants' own attitudes and behaviour (including reported attitudes regarding appropriate marriage age and willingness to contribute to a charity that campaigns against child marriage), but did not substantially influence their beliefs about attitudes or practices prevalent in their community. Follow-up surveys conducted 5 and 10 months after the intervention show an increase in early marriage among adolescent girls within treatment households. These perverse effects are driven by households where the father and family elders were informed about the new law but are absent in households where only the mother is informed. The findings highlight a) the existence of informational frictions within housholds and b) the risk of a backlash effect against a law that contradicts traditional norms and practices.