The United States no longer has pure “at will” employment because the law prohibits the employer from terminating or otherwise taking action against an employee in certain situations. The prohibited reasons include firing you because:
  • of your race, color, religion, sex, national origin, citizenship, age, disability, or genetic test information under federal law (some states/localities add a few more categories like sexual orientation);
  • you make certain kinds of reports about the employer to the government or in limited circumstances to specified persons in the employing company itself (known as whistle-blower protection laws);
  • you participate in union organizing activities;
  • you use a right or benefit the law guarantees you (e.g. using leave under FMLA);
  • you filed a bankruptcy petition;
  • your pay was garnished by a single creditor; and
  • you took time off work to attend jury duty (in most states).

The exact list of prohibited reasons will vary by state. An employer may, however, terminate you for any reason not prohibited by law. In other words, unlike some European nations, an employer does not need just cause (i.e. need to prove you did something wrong or are a poor performer) to fire you.

The only potential illegal discrimination you seem to raise in your case is age discrimination. Under federal law, an employer with at least 15 employees may not discrimate against you because of your age if you are at least age 40. A number of states also prohibit that and apply it to smaller employers than federal law does. An employer treating you adversely, including refusing to promote you or paying you less, simply due to your age would violate those laws. The issue is that you have to be able to prove the illegal discrimination. If the employer has a discernable pattern of favoring younger employees, for example, that can help even if there is no express proof in your particular case that age was the issue preventing you advancement in the company. If you think you have been discriminated against because of your age, you ought to see an attorney who litgates illegal employment discrimination cases. Many will give you a free consultation and you can find out if you have a claim to pursue and how to document instances of potential discrimination to support future claims that you might have. You need to act promptly after discrimination has occurred. Depending on the state in which the discrimination took place, you may have as little as 180 days after the discrimination occurred to make your complaint to the EEOC and/or state agency that enforces illegal discrimination employment claims. If you fail to make the complaint on time you may be barred from suing the employer.