The Emancipation Proclamation was never challenged in court. To ensure the abolition of slavery in all of the U.S., Lincoln also insisted that Reconstruction plans for Southern states require abolition in new state laws (which occurred during the war in Tennessee, Arkansas, and Louisiana); Lincoln encouraged border states to adopt abolition (which occurred during the war in Maryland, Missouri, and West Virginia) and pushed for passage of the Thirteenth Amendment. Congress passed the 13th Amendment by the necessary two-thirds vote on January 31, 1865, and it was ratified by the states on December 6, 1865. The amendment made chattel slavery and indentured servitude illegal.