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.
The concept of employer grades for certain work positions is not legally controlled by external laws in employment law. What I mean by this is that these "grades" aren't mandated or regulated by employment law, so it's not a legal construct. Job descriptions are also not legal constructs, but merely guidelines to assist an employer and employee in understanding what the job functions are.
So yes, it is legal to tell you the parameters of the grades or not tell you the parameters of your grade. All these things are discretionary employer functions. Now, all the said, why then do employers tend to create these things and abide by them if they don't have to? Consistency helps to avoid allegations of discrimination based on race, religion, gender, age, disability or recent FMLA use; whereas, a lack of consistency can basically invite an allegation of discrimination.
So, if you can allege that the actions being taken against you (disparate or differing treatment) are or could be related to one of the protected categories that I mentioned THEN the matter of them not following their guidelines on grades becomes an actual legal issue that can be dealt with through a complaint to HR, and if not resolved, a complaint to the EEOC in your state.
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