Hi, thanks for submitting your question today. My name is XXXXX XXXXX I’m happy to assist you with your question today.
Because you are a union member, you have all the rights under the collective bargaining agreement to "just cause" in your employment - this means a fair and accurate treatment and procedure - along with a right to be heard and file a grievance without retaliation. Also, you need to file a grievance against the company for this particular supervisor's treatment as creating a hostile environment and diminishing your contractual right in employment - you have the absolute right under the contract
to file grievances and cannot be retaliated against for doing the same. Likewise, if the grievance is rejected, you can request your union file arbitration
The other option is you and the other workers can file an unfair labor practice charge with the NLRB alleging this supervisor's treatment is in retaliation of your expressing your collectively bargained right to file grievances. These are free of charge and you can follow the process at this link http://www.nlrb.gov/what-we-do/investigate-charges .
I believe this answers your question. However, if you need clarification or have follow-up questions regarding this matter, I will be happy to continue our conversation – simply reply to this answer. If you are otherwise satisfied with my response, please leave a positive rating as it is the only way I am able to get credit for my answers. Thank you, XXXXX XXXXX wish you all the best with this matter.