I'm not sure what your point was, but this example flies counter to a negative take on public opinion overturning law. It was BY LAW that southern blacks, in particular, were most egregiously discriminated against. And it was the use, misuse, and abuse of said law that enabled a corrupt power structure to (re)emerge after the civil war. The reason we called it institutional racism was because it had the blessing and codification of the institutions. What beat that back was public opinion. People protested, got on TV, showed the travesty of the whole thing and that eventually led to it being unpopular to be a racist and/or support racist policies. Ultimate, those bad laws had to be struck down, but it was public opinion that made that happen. We may not like to admit it, but the majority always rules. It shouldn't be that way and the Constitution was designed to minimize the effect of mob rule. But in the end, politicians advocate policies based almost entirely on what they believe will get them (re)elected.