Thank you very much for your reply. I am so sorry to hear about all this and agree that it is extremely unfair.
In addressing your concerns, I hope you will not mind if I start with the negative. Employers enjoy vast discretion with regard to the way in which they are permitted to run their business. Generally speaking, there is no law which prohibits unfair treatment or bad management, and employers can hire, fire, demote and promote for virtually any reason they choose.
The notable exceptions here are in the area of public policy. Employers may not demote or discriminate on the basis of a legally protected trait, such as race, religion, gender, age or disability. Employers also may not take adverse employment action in retaliation for employees engaging in certain legally protected activities (I'll touch on that more in a second).
You indicate that someone younger than you has been promoted, and that is perhaps indicative of age discrimination, but as you likely suspect, you will need more evidence than that to prevail on a discrimination claim. Plaintiffs always bear the burden of proving their case by a preponderance of the evidence, and so unless you have additional evidence of discriminatory intent (i.e. a company-wide practice of favoring younger employees, derogatory comments made about your age, etc.) you would not fair well in court. IF you do desire to make an age discrimination claim, a pre-requisite to that would be to file a complaint with the EEOC, which you can learn about here: http://www.eeoc.gov/employees/howtofile.cfm
The area of concern I see is with regard to your "exempt" status. The Fair Labor Standards Act begins with the presumption that all workers are entitled to overtime. Only those workers who have positions that fall within a specific statutory "exemption" can be paid a flat salary without regard to the number of hours worked.
The most common exemptions are those for managerial employees, administrative employees who run the company, and "professional" employees, such as doctors, lawyers, and CPAs. See here for more information on the common exemptions: http://www.dol.gov/elaws/esa/flsa/screen75.asp
The job duties you have described would NOT appear to fall within any statutory exemption from overtime. However, it is impossible for me to make any sort of definitive statement with regard to your particular position.
I would strongly recommend that you consult with a local employment law attorney to see about making a claim for unpaid overtime. The good thing about making such a claim, and what I was alluding to above, is that employers are legally prohibited from retaliating against an employee for filing a wage claim. This is one of the few exceptions to the general principle that employers can manage their business as they see fit--employers cannot take adverse employment action against a worker for asserting their right to be paid overtime.
Filing a claim for unpaid overtime would give you a plausible argument that any subsequent adverse employment action taken against you was in retaliation for your claim. If you could link a demotion or termination to your overtime claim, that would have an entirely separate claim for damages, regardless of how your overtime claim itself resolved.
To locate an employment law attorney in Illinois who can assist you with your claim, see here: http://www.martindale.com/labor-employment/s-Illinois-lawyers-cities.htm
Again, while most of what you describe is not illegal unless you can specifically link it to age discrimination or some other specifically unlawful motive, the limited facts you have provided would tend to indicate that you may be improperly classified as "exempt." That being the case, your best course of action would typically be to file a wage claim, which would entitle you to unpaid overtime and largely insulate you from further adverse employment action, which you could argue was retaliatory.
Please do not hesitate
to let me know if you have any questions or concerns regarding the above and I will be more than happy to assist you further.
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