Museums are important public sites for the authentication and presentation of heritage in Western cultures. The authority of museums is derived from their long history as repositories of material culture and as agents of identity formation, nationalism, and most recently, social inclusion. But in a country such as Canada where global economics and popular culture combine with an unprecedented influx of immigrants, how society imagines itself and how the nation articulates its community and its heritage is changing radically. Issues of power, meaning, authenticity and citizenship have threatened the museum’s representational authority. How are Canadian museums responding to these changes, and is their authority now up for debate? Or is the need to assert authority a problem in itself and can museums evolve a new type of discourse about heritage? This paper investigates museum authority inherent in its simultaneous roles as voice of the state and as a public space for opinion and meaning making. It focuses attention on Canadian museums and government policies that have influenced their authority, in particular, theoretical implications of the current drive for ‘social cohesion’. An exhibit on the Underground Railroad and African-Canadian history at the Royal Ontario Museum in Toronto is examined to consider how museums as instruments of the state can be re-tuned as sites of public identity discourse and social inclusion