The Future of the Progressive Personal Income Tax: How High Can it Go?

The author draws on economic theory and evidence to build the case for considering boundaries for the high-income tax rate. Because of behavioural responses to higher rates, an upper boundary arises; above it, the revenue loss from behavioural responses outweighs the revenue gain from the higher rate. However, this upper boundary can be pushed upward through stronger enforcement and may vary with non-tax considerations, such as shifts in the demand for and supply of highly skilled workers. This framework suggests that if higher rates are to raise revenue in Canada, serious measures must be taken to increase the upper boundary.