These facts do not by themselves establish unlawful bias.
Absent a union contract that provides for a schedule of employee compensation, employers are free to pay what they choose or what the market requires, so long as wages meet the legal minimum established by law. Varying market factors can account for divergences and variations: seasonal, length of assignment, work conditions, availability of other sufficiently skilled workers, etc. If there is enough data to make reliable statistical analyses, variances that align with race, gender, etc may be revealed that way. But a handful of instances with widely varying data is not ordinarily sufficient to establish unlawful bias.
Talk with a local employment attorney for a fuller discussion and analysis.
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