Adjunct Law Prof reports on new legislation in Maryland recognizing a privilege for communication between a union and an employee received in confidence when the union is acting in a representative capacity concerning an employee's grievance. Maryland Joins in Recognizing a Labor Relations Privilege. As noted in his blog, Mitchel Rubinstein has written extensively on this issue. Labor Relations Counsel also has a discussion of the new law here.
The same issue is currently pending before the Supreme Court of Alaska. Is there a privilege for union member/union rep discussions?
Update: The Alaska Supreme Court has recognized a labor relations privilege. The court's decision is available here.