What violations of the Constitution were there?
Please name them.
The only violation that the South could cite was the election of Lincoln, who they saw as a threat to their slave empire.
Article 4, Section 2.
"No person held to service or labor in one state, under the laws thereof, escaping into another, shall, in consequence of any law or regulation therein, be discharged from such service or labor, but shall be delivered up on claim of the party to whom such service or labor may be due."
Amendment X
"The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people. "