I think the term is union busting where they prevent
formation of unions. This way, the
management will be able to have more control over how things run without union
interference. Other methods could be
blacklisting them to ensure they won’t work for other companies.
Mills vs. Board of Education was a lawsuit filed against the District of Columbia in the early 70s. The lawsuit was on the behalf of 7 disabled children who were denied access to a public school education because it was thought that their needs were too great for them to be able to be educated in a public school setting (it was also said by the Board that it would be too expensive to educate them).