Under Labor Code 1126, a collective bargaining agreement is entitled to be enforced under the same laws as any other contract.
Your facts suggest that your union has diverted a portion of your wages to a purpose for which you have not given any consent. However, if the union board voted to make such a contribution, then absent the member's removal of the board, the contribution would be lawful, because all union members are subject to both the union contract, and the rules created by the union board in any formal resolution.
The trick with union issues is to find the relevant resolution or contract provision, or conversely, to show that no resolution or contract provision exists. This can be a daunting task, since unions are typically pretty closed fisted when it comes to providing document access to members.
You could contact the U.S. Department of Labor -- Employee Benefits Security Administration and request an investigation. See this link.
Alternatively, you would have to try to get a union rep to give you access to the entire collection of active union documents concerning your pension rights, and then try to confirm or deny the existence of the 2% contribution provision.
If you can't find anything, then you may have a viable lawsuit against the union.
Hope this helps.
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