Did you know...
The United States Supreme Court has original (rather than appellate) jurisdiction over "all cases affecting ambassadors, other public ministers and consuls, and those in which a state shall be party"? That means that when a state sues another state, the complaint is filed in the Supreme Court.
Needless to say, this doesn't happen very often. But it did happen on Thursday:
"The state of Montana asked the Supreme Court on Thursday to allow it to sue [sic], directly in the Court, a lawsuit claiming that the state of Wyoming is illegally withholding waters from the Powder and Tongue Rivers. The lawsuit, an Original motion to file a bill of complaint along with a complaint, has not yet been assigned a docket number.
I'm tickled by this because I like the idea of original Supreme Court jurisdiction (after all, improper original Supreme Court jurisdiction gave us Marbury v. Madison), and it's particularly fun because just last week I read another state-vs-state water rights case originally filed in the Supreme Court in which the Court was called upon to interpret a decree from King George.
Law geekiness aside, however, I think a better system for resolving state-vs-state disputes would be simple armed conflict.
UPDATE: When I was talking about the King George case with my co-clerk we wondered how these cases actually proceed, since it's difficult to imagine the Justices dealing with things like discovery. We quickly discovered that the Court appoints special masters who basically act as trial judges and make recommendations to the Court. A SCOTUS blog post on these Special Masters is here. Apparently these filings happen more often than I thought -- there have been two such cases decided in the last few years, one in 2003 and one in 2005.