From the abstract:
Too often women encounter the argument that pay disparity is the outcome of market forces and not sex discrimination. Salary differentials are attributed to individual pay demands, bargaining effectiveness, external counteroffers and/or prior salaries. These are just a few examples of market justifications employers raise to explain why similar workers performing the same job are compensated differently.
This paper argues that, in most cases, market justifications for pay disparity in equal pay for equal work litigation should be rejected. The paper then takes on the more ambitious project of proposing an alternative model of gender discrimination, which is not restricted to causation.