Published online by Cambridge University Press: 03 July 2019
Tolerance – respecting individual choice and differences among people – is a prominent feature of modern European culture. That immigrants embrace this kind of liberal value is arguably important for integration, a central policy goal. We provide a rigorous study of what factors in the ancestral countries of second-generation immigrants – including formal and informal institutions – predict their level of tolerance towards gay people. Using the epidemiological method allows us to rule out reverse causality. Out of the 46 factors examined, one emerges as very robust: a Muslim ancestral background. Tolerance towards gay people is lower the larger the share of Muslims in the country from which the parents emigrated. An instrumental-variable analysis shows that the main mechanism is not through the individual being a Muslim, but through the individual being highly religious. Two additional attitudes among people in the ancestral country (valuing children being tolerant and respectful, and valuing children taking responsibility), as well as impartial institutions in the ancestral country, predict higher individual tolerance. Our findings thus point to an important role for both formal- and informal-institutional background factors in shaping tolerance.