According to the Act, differences in pay between female and male job classes are allowable if the differences can be attributed to differences in bargaining strength:

• After pay equity has been achieved in an establishment, the Act does not prevent differences in compensation between a female job class and a male job class if the employer is able to show that the difference is the result of differences in bargaining strength [8. (2)].

The Tribunal has noted that the defence of bargaining strength could not be raised to explain wage differences until the employer had achieved pay equity for all employees in its establishment York Region Board of Education v. Canadian Union of Public Employees, Local 1734, 1995 CanLII 7202 (ON PEHT).

While the Act does not specifically define “differences in bargaining strength,” the Tribunal has interpreted bargaining strength to mean the ability of a bargaining unit to exercise power on behalf of all its members. In this case, the preferred interpretation refers to difference between different bargaining units, as opposed to differences within the same unit. Furthermore, due to the remedial purpose of the Act, any exception should be narrowly defined and the onus is on the employer to provide evidence that conditions do in fact exist that warrant the application of the exception BICC Phillips Incorporated v. Group of Employees, 1997 CanLII 12223 (ON PEHT) and Stevenson Memorial Hospital v. Ontario Public Service Employees Union, Local 360, 2000 CanLII 22419 (ON PEHT).