Good afternoon Joshua,
I'm Doug, and I'm very sorry to hear of your situation.
Unless you have a written contract of employment with your employer, which guarantees your position with the company for a set period of time and at a given wage, then you are considered an employee-at-will. This means that there is likely little protection afforded you relating to unreasonable supervisors/bosses, as well as the typical workplace politics and drama which can be so troublesome.
In Illinois, employees are presumed to be "at will." At-will employees may be terminated for any reason—at any time, even a mistaken reason, they can have their hours or pay decreased and they can suffer a cut in their benefits, so long as it's not illegal or unlawfully discriminatory. Generally, employees who work under an employment contract can only be terminated, or have significant changes made in their work conditions, for reasons specified in the contract. In your state, an employment relationship is at-will unless there is a defined duration for the employment contract or if the contract permits termination by the employer only under specified circumstances.
Unlawful discrimination would include an employer discriminating based upon a person’s Ethnicity, Color, Religion, National Origin, Gender or Disability.
Placing you into an assistant manager position when a manager's position was not available was entirely lawful. And the fact that you are offered less as a salary, or offered less for your wages, is also lawful under both California employment laws and the federal employment laws and acts.
I wish you the best in 2013
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