The EEOC enforces the federal laws that prohibit illegal discrimination of employees by their employers. Those laws make it illegal for a private employer with at least 15 employees, and any state or local government employer, to discriminate against an employee because of the employee’s race, color, national origin, citizenship, age (if the employee is age 40 or older), sex, disability, or genetic test information. An employee who has been subjected to illegal discrmination under federal law must file a timely complaint with the EEOC before the employee may file a lawsuit against the employer. For employees in Washington state, that deadline is 300 days after the alleged act of discrimination took place. If you fail to file the complaint in time, you are barred from suing the employer for that alleged act of illegal discrimination.
Moreover, for certain claims of harassment/hostile work environment you need to first make a complaint to the appropriate person(s) in the company and give the company a chance to remedy the harassment. It is only when the company fails to stop the harassment that the employer would be liable for those instances of harassment. After all, the company cannot fix what it does no know about.
Washington State also has a law that bars illegal discrimination by employers. It applies to employers with at least 8 employees. It makes it illegal for the employer to discriminate on the basis of age, sex, marital status, sexual orientation, race, creed, color, national origin, honorably discharged veteran or military status, or the presence of any sensory, mental, or physical disability. If you want the Washington State Human Rights Commission (WSHRC) to investigate the alleged illegal discrimination you must make your complaint within 6 months of the alleged discrimination. Unlike the federal law, however, you do not have to first make a complaint with the WSHRC before you may sue. It appears that you may have two years from the date of the alleged discrimination to sue the employer, but verify that with an employment law attorney in Washington state.
If your employer has at least 15 employees, you may file just one complaint with either the WSHRC or EEOC and if you indicate in your complaint that you wish to cross file with the other agency then the filing will forwarded to the other agency, too. This way you would only have to file with one agency and it would count as filing with both. If you do that, you need to do it within the shorter 6 month period that Washington has for these filings.
What this all means is that you do not want to wait long to notify HR of alleged illegal discrimination and to file with the EEOC or WSHRC. If you wait too long, you may lose the right to sue the employer and, significantly, you fail to put an end to the discrimination you are facing because the company cannot address discrimination it does not know about.
I suggest that you promptly see an employment law attorney about this to get started in organizing your claims. Ask the attorney for advice on how best to word your complaints to HR and get the attorney to help draft your complaints to the EEOC and WSHRC. How you frame these complaints can be important later on if you have to sue the employer. Focus in particular on the most recent events — those within the last year or so, as those are the ones for which you could still possibly sue under both federal and state law. The events in the last two years are relevant for claims under state law. The older events are not totally irrelevant but you don't need to get into those in great detail now since they'll be too old for you to pursue in court — but they will provide useful background to help show a longstanding pattern of discrimination. So don't worry about going back all 7 years at this point. Organize the most recent events and get to an attorney for advice and assistance.