While each of the three major Supreme Court cases deals with a different segment of the workforce (Lehnert with the rights of public employees under the Constitution, Ellis with railway and airline employees under the RLA, and Beck with the rights of most other employees under the NLRA), the principles behind employee dues protections are essentially the same. The legal theories supporting these cases vary slightly, and the procedural requirements are different, but the underlying principle is that union dissenters cannot be compelled to contribute monetary support to those activities which are not germane to the unions function within the workplace.