Boss
Take a Memo:
Yes it was legal to own other humans. And the South wanted to make sure that would be a right granted to them in perpetuity rather than have to wonder if that right might someday be taken away. I'm not trying to retroactively apply any law
Well, yes you are, hard head!
The South was protecting their constitutional right to property by ruling of the US Supreme Court. Slavery did not become illegal until ratification of the 13th Amendment. You're attempting to apply it to 1861.