"I don't even believe that once a State had been admitted as a slave State, that it could change its status to being a Non slave state by a vote of the people. Nor could a non slave State become a slave State. Can someone answer that question under those various compromises. Could Missouri, which was admitted as a "slave State", have, by a vote of its legislature, or popular vote, become a "free State" as allowed by the Constitution, without violating those congressional compromises of the times?"
TR,
I could be wrong since I have not researched it but I think that after the hostilities of 1861 to 1865 that the states in rebellion did not have any problem in renouncing slavery as a prerequsite to coming back in to the Union fold.
FC