Minimum wage laws have been used to by racists around the world to discriminate against black people competing for jobs against whites. In America, it was first implemented under the Davis-Bacon Act of 1931.
And Congressmen are on record saying that “cheap colored labor” was a threat to white construction workers. And unions didn’t like that. So, naturally, Congressmen did what the unions wanted and it hurt black Americans.
It still does. But liberals don’t let evidence get in the way of patting themselves on the back for caring about the very people they hurt. Thomas Sowell calls this “public policy for the purpose of self-congratulation.”