Even though it appears that there is just one law that covers discimination in reality there are several overlapping laws. Gender based discrimination has taken many forms including different pay rates. The legislature addressed the differing pay rates and enacted the Equal Pay Act, which differs and is in addition to anti discrimination statutes under Title VII of the Civil Rights Act. Under federal and state law the practice of paying different pay rates depending on the employee's gender is unlawful. The pay rate must be the same for both genders doing the same job, with a few exceptions.

The Federal Equal Pay Act specifically states that no employer having employees subject to any provisions of 29 USC section 206(d) shall discriminate, within any establishment in which such employees are employed, between employees on the basis of sex by paying wages to employees in such establishment at a rate less than the rate at which he pays wages to employees of the opposite sex in such establishment for equal work on jobs the performance of which requires equal skill, effort, and responsibility, and which are performed under similar working conditions, except where such payment is made pursuant to (i) a seniority system; (ii) a merit system; (iii) a system which measures earnings by quantity or quality of production; or (iv) a differential based on any other factor other than sex: Provided, That an employer who is paying awage rate differential in violation of this subsection shall not, in order to comply with the provisions of this subsection, reduce the wage rate of any employee.

Meaning that unless there is some sort of seniority system, or pay is based on merit, or pay is based on the quantity or quality of the production, or pay is based on something other than the person's gender, the pay rate has to be the same for both genders. By other the courts have interpreted to mean that the basis for paying a different rate for men and women is a legitimate neutral factor adopted for reasons other than paying men and women different rates.

The equal pay act also prohibits labor organizations, their agents, representing employees of an employer from discriminating an employee in violation of the equal pay act.

If there is discrimination then the wages owed are treated as if the employer had failed to pay minimum wage or overtime pay. Which subjects the employer to liability not only for wages due, but also for attorney fees if the discriminated employee files suit.

Unlike a sexual discrimination case, in these types of cases the employee is not required to prove intent on the part of the employer. If men and women do the same job and have substantially the same amount of skill and experience, then the pay rate must be the same.

Employers are allowed to pay different rates for different shifts, if women happen to dominate one shift and men the other, then it is permissible, as long as the night shift is the higher paid shift and it is clearly not the intent of the employer to discriminate.

Employers are not permitted to require greater contributions to pension plans from women, even though women are the gender with the higher life expectancy.

The going market rate is not an excuse and not permitted as means to pay men more than women.

The California Equal Pay Act is substantially the same as the federal act and covers all employers, regardless of size. A claimant is required to file suit within two years or if the act was willful within three years. The claimant is entitled to backpay, an equal amount in liquidated damages, interest, costs, and attorney fees. The courts have rejected comparable worth claims under the Equal Pay Act where the employee seeks equal pay for dissimilar jobs on the theory of comparable worth for the respective jobs.

Some organizations have resisted paying men and women equally on the grounds that men have families to support, this argument has been rejected by the courts and the courts don't look favorably to such defenses to gender based pay discrimination.