I'm taking this here as it seems like such a fascinating scenario. Let's say Andrew Jackson and the early Democrats push through a constitutional amendment electing SCOTUS from 9 districts apportioned by population. Here's the background from another poster:
If the Supreme Court was elected, Dred Scott would have likely resulted in a ruling declaring the institution of slavery unconstitutional, since the North would have had more than 5/9ths of the apportion-able population.
Then what happens? Assuming Buchanan (or another Democrat) is president, do they enforce or do thy try to ignore it? Does the South secede and/or declare war after the decision? If Buchanan refuses to enforce, do Northern abolitionists secede or even attempt to overthrow the federal government and occupy DC?