I'm not familiar with the MPDF and not disagreeing w/ your thoughts of protective unions, to an extent...
With that in mind, Union strength is not created from thin air. It's the response/result of extreme abuse of autoworkers, steelworkers, electrical, police, fire, etc by the company or governing entity.
Far too often, w/in election cycled Management - sacrificing a firefighter, medic or officer to quell a fickle mob is political and far from legitimate review boards.
There is a reason unions must be protective. It's a process. As is our legal system, better to let a few criminals walk than to trample on the innocent and even still innocent are found guilty.
I.e. fruit of the poisonous tree.
Again, not disagreeing w/ the basis of union strength though far from supportive of a weak union.