Doug Mataconis makes this point in his examination of Ron Paul’s statement that he wouldn’t have voted for the 1964 Civil Rights Act because it violates “property rights” of the owners of establishments that chose to discriminate:
It’s also worth noting that Plessy v. Ferguson involved a Louisiana law that was designed to prevent the Pullman Company from offering equal seating options to blacks. That, in fact, was the entire purpose of Jim Crow laws. Even if, for example, the Woolworth’s in Greensboro, North Carolina had wanted to serve the four black college students who sat down at their lunch counter on February 1, 1960, the laws in place at the time told them that they couldn’t. Racial segregation in the South wasn’t a product of the free market, it was the product of a state imposing racial prejudices under the threat of criminal prosecution. For that reason alone, it was a violation of the 14th Amendment and the Federal Government was entirely justified in trying to bring it down.
Both of the Pauls fall back on the view that it’s oh-so-awful that the federal government might tell some private business owner that they can’t run a business however the hell they please, but they conveniently ignore the fact that state governments were imposing the same tyranny upon the same business owners for decades. I’m willing to imagine that the Pauls truly believe, as Goldwater did, that the Civil Rights Act is partially unconstitutional, and that the political convenience that many of their supporters aren’t big fans of that measure isn’t the reason they would have opposed it. So, the right question for the Pauls isn’t “would you have voted for the Civil Rights Act”, but “what would you have done about Jim Crow laws?” And if they can’t be as full-throated and precise about how the federal government had a legitimate role in ending that kind of tyranny, then not only do they deserve to be called racists, but Libertarians who support them have a lot of explaining to do.