Five justices were nominated by Lincoln during Civil War (probably replacing Southerners who left the Court when their States seceded); three were nominated in the 1845-47 timeframe. While it was a 5-3 decision, two of the dissenters were Lincoln appointees.
The case is still precedent; it has not been overruled.
Still did not address the actual power behind it, i.e. it having as much authority (none) as a similar ruling from a British judiciary in 1776.
Not to mention the fact that placing all power with the SCOTUS has given us a country no longer bound by the Constitution, but by the whim of five SCOTUS members, many of whom have admitted that they view the times (or foreign law) as a guide to their decisions, rather than the original intent of said document. You look to the law as a guide when we are now a nation of MEN, men who advocate the reduction of true liberty at every turn.