His research has been animated by an ongoing interest in the politics of social solidarity, as represented by public support for redistributive programs that help the most vulnerable in society. He has analyzed the impact of a variety of factors that matter for social policy. His first book, Poverty, Politics and Policy, examined the politics of poverty in Britain, with particular attention to the role of ideational change. In The Welfare State and Canadian Federalism, he turned his attention to the design of political institutions, analyzing the potential impact of constitutional change on the redistributive role of the Canadian state. With colleagues, he has also explored the tension between globalization and redistribution in Degrees of Freedom: Canada and the United States in a Changing World, as well as the impact of growing inequality in Inequality and the Fading of Redistributive Politics.
Keith's primary focus in recent years has been on multiculturalism and social solidarity. Much of this work challenges the common assertion that the growth of ethnoracial diversity inevitably weakens social solidarity, weakening the public’s support for programs that extend benefits to newcomers and minorities who are not seen as part of 'us'. Two early co-edited contributions are Multiculturalism and the Welfare State: Recognition and Redistribution in Contemporary Democracies and then Belonging? Diversity, Recognition and Shared Citizenship in Canada. More recently, he and Will Kymlicka focus on the potential sources of support for an inclusive solidarity in The Strains of Commitment: The Political Sources of Solidarity in Diverse Societies. With Allison Harell, they are pursuing this theme in research on perceptions of membership, belonging and solidarity.
In addition, Keith co-directs (with Will Kymlicka) the Multiculturalism Policy Index project, which monitors the evolution of multiculturalism policies across 21 Western democracies.
This project analyzes public attitudes towards the deservingness minority groups for welfare support, based on a specially designed survey conducted in Canada in August-September 2017.
The Multiculturalism Policy Index [MCP] is a scholarly research project that monitors the evolution of multiculturalism policies in 21 Western democracies. The project is designed to provide information about multiculturalism policies in a standardized format that aids comparative research and contributes to the understanding of state-minority relations.
This project examines change in ethnic rivalries in historically contested cities, where established status hierarchies are challenged by “political newcomers” such as immigrants and other newly mobilized ethno-cultural communities.