I don’t know if Hillary is just ignorant or simply pandering to her low IQ supporters.
Even after the Civil War the legislature nor the courts could free slaves. It took a Constitutional amendment to do that.
The Supreme Court can not overturn a Constitutional amendment (even if they wanted to and there is no evidence anyone wants to).
So she is pandering.
Now if she said they could overturn the Civil Right laws of the 1960s which in fact took away individual rights as to whom they would associate with, she may have a point.
Hillary is pandering. She has not thought through the nuances or legal basis for the Civil Rights Act of 1964. She’s not really that smart though we are told she’s the smartest woman in the world.