The Northwest Ordinance of 1787 was re-authorized in 1789 by the 1st Constitutional Congress with the appropriate edits and other minor changes to reflect the structure of the new form of government. Though all of the old Northwest Territory is now within the jurisdiction of states, aspects of the ordinance, and other pre-consitutional law, remain in effect today.
The Northwest Ordinance of 1787 was also known as the "Freedom Ordinance." Care to hazard a guess what that was the case?
That's all well and good, but reauthorization wouldn't rescue its unconstitutional sections from the attention of the Supreme Court.
The exclusion of slave ownership from the Northwest Territories was unconstitutional.