School-bus drivers Billie McClinsey and Brad Mayer didn’t like being represented by the Teamsters and wanted to put the matter to a vote. That should have been straightforward. Federal law provides that if union opponents collect signatures from 30% of their co-workers, they can ask the National Labor Relations Board to schedule a vote. But the process is frequently made convoluted and oppressive. As a result, Messrs. McClinsey and Mayer are trapped—likely indefinitely—in the union they oppose. The NLRB is soliciting comments on proposals to lift barriers that limit workers’ right to remove a union. Messrs. McClinsey and Mayer work...