Only "at-will" employees can be terminated without cause. If your friend is a union member, there are restrictions on how an employer may terminate an employee, which are spelled out in the union contract. Your friend needs to speak with his union representative immediately.
They say you get what you pay for, and this response is free, so take it for what it is worth. This is my opinion based on very limited information. My opinion should not be taken as legal advice. For true advice, we would require a confidential consultation where I would ask you questions and get your complete story. This is a public forum, so remember, nothing here is confidential. Nor am I your attorney. I do not know who you are and you have not hired me to provide any legal service. To do so would require us to meet and sign written retainer agreement. My responses are intended for general information only.
You should immediately contact your union steward (representative).
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If this whole incident has been "cooked up" as a pretext for discrimination or retaliation (for whistleblowing, for example), your friend MAY be able to file a lawsuit in court or go through union grievance-arbitration procedures.
Talking to an experienced labor and employment lawyer, as well as the union steward, may be warranted in this situation. A 25-year job is at stake and your friend should educate himself on all the angles.
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If the union cannot assist you, it is unlikely you can sue the employer for wrongful termination because it is allowed to terminate you for any reason or no reason, and even an erroneous reason. You might have some rights against the individuals involved if you can prove this was all a big lie, but then you need to decide if suing another person who may not have many assets makes any sense.
Good luck to you.
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