Coworker thinks there is discrimination in pay?

I do not know about the discrimination part unless you have something under the Fair Pay Act. You would only have those grounds if the men in the workplace are earning more than you and all of the women are earning less then the male counterparts and doing the same exact work. Would also need to prove the men they hired with less experience than you started at a much higher salary. You need to understand something. Although the salary range may be from X to X.... Hiring managers will ALWAYS try to get the individual on the low end of the scale regardless of their experience. Thereafter, someone with the experience who obviously should have been offered on the high end, but they accepted in the low end they laugh in the back office about it.