http://en.wikipedia.org/wiki/Supreme_Court_of_the_United_States#Size_of_the_Court<snip>
The United States Constitution does not specify the size of the Supreme Court, but in Article III it authorizes the Congress to fix the number of justices. The Judiciary Act of 1789 called for the appointment of six justices. As the country grew geographically, Congress increased the number of justices to correspond with the growing number of judicial circuits: the court was expanded to seven members in 1807, nine in 1837 and ten in 1863.
At the request of Chief Justice Salmon P. Chase, Congress passed the Judicial Circuits Act (1866) which provided that the next three justices to retire would not be replaced; thus, the size of the Court should have eventually reached seven by attrition. Consequently, one seat was removed in 1866 and a second in 1867. However, this law did not play out to completion, for in the Judiciary Act of 1869,<73> also known as the Circuit Judges Act, the number of justices was again set at nine, where it has since remained.
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I think the United States has grown rather significantly since 1869. The size of both the Senate and the House has grown over the years. Does it really make sense that
nine people should wield such a vast amount of power? In all honesty, over the past several years, we've seen that it can boil down to just one or two justices making such a huge impact.
We didn't have 50 states back in 1869. We sure as hell didn't have nearly 400 million people back then.
Maybe it is time to update the SCOTUS.