What steps can I take if I am paid less than a coworker of the opposite sex for substantially similar work in California?

You have legal protections under California's Fair Pay Act. You can take action by gathering evidence of the pay disparity and filing a formal complaint with a state agency or by consulting with an attorney to file a lawsuit. Here are the steps you can take: Step 1: Gather Your Documents and Information Collect your pay stubs, official job description, and performance reviews. Make detailed notes about your daily tasks, skills used, level of effort, and responsibilities. If possible, document the same for your coworker. Under California Labor Code Section 232, your employer cannot prohibit you from discussing your wages with coworkers. Step 2: File a Complaint with the Labor Commissioner's Office You can file an Equal Pay Act complaint with the Division of Labor Standards Enforcement (DLSE), also known as the Labor Commissioner's Office. You must file within two years of the date of the unequal pay, or three years if the violation was willful. You can find the complaint form on the website for the California Department of Industrial Relations (DIR.ca.gov). Step 3: File a Complaint with the Civil Rights Department (CRD) As an alternative, you can file a discrimination complaint with the California Civil Rights Department (CRD). The CRD enforces the Fair Employment and Housing Act (FEHA), which also prohibits unequal pay based on sex. You have three years from the last act of discrimination to file a complaint. You can start the process on the CRD.ca.gov website. Step 4: Consult with an Employment Law Attorney An attorney can provide a confidential assessment of your claim, explain your options, and help you decide the best course of action. They can represent you before state agencies or file a lawsuit directly in civil court. Lawsuits for these claims generally must be filed within two or three years of the violation. Important Details and Nuances: An employer can legally justify a pay difference if it is based on a seniority system, a merit system, a system that measures earnings by quantity or quality of production, or another bona fide factor other than sex, such as education or experience, that is job-related. It is illegal for your employer to retaliate against you for filing a complaint or inquiring about wage differences. Warnings and Limitations: There are strict deadlines, called statutes of limitation, for filing claims. If you miss a deadline, you may lose your right to take legal action. Proving your work is "substantially similar" requires a detailed comparison of skills, effort, responsibility, and working conditions. This is general information and does not constitute legal advice. For complex situations, consult with a qualified California attorney.