Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and over 20 years of experience in the legal field. I’m happy to be of assistance.
Workplace harassment/hostile work environment is actually a much more restricted term than it sounds like it would be. It certainly seems like it should apply in your situation. However, the Supreme Court of the United States was very specific when it chose to define these terms, noting that our employment laws are not meant to be a civility code. The Court held that our laws don't regulate workplace politics, but only concerns illegal forms of discrimination. That means that you must have both the harassing behavior and evidence showing a discriminatory motivation.
Now, while being treated differently than others is a form of discrimination, not all forms of discrimination are illegal. For instance, it's not illegal to promote one person over others, even then though that is technically a form of discrimination or preference. One person was promoted and others were not. What matters is the basis for that decision.
So, on your facts, just being the only person treated in the fashion that you were is not, by itself, illegal discrimination. Instead, you have to also establish that the underlying reason for the treatment was your race, religion, gender, age, disability or recent FMLA (medical leave) use. Other forms of discrimination revolve around retaliation for your use of certain legal rights, like OSHA complaints, worker's compensation claims, Wage and Hour complaints to the state or Union activity/organization.
The point though is that without showing one of these illegal motivations, there would be no cause of action against the employer for the treatment you described.
If you can suggest one of those motivations (as you differ in some way from all the other managers that were not targeted), then you may have a cause of action. You'd need to contact the EEOC, Department of Labor, OSHA or a worker's compensation attorney, depending on which factor was discriminated against, because you'd need to quickly file a claim.
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