How do states sue each other?
<p>As I understand it one of Scotus jobs is to mediate inter-state litigation. Did this happen with equal regularity over the years or was this something that happened mainly when the union was new?</p>
<p>Is it therefore at least in theory possible for two states to have contrary laws and scotus be forced to make a value judgment contrary to state law to resolve some dispute?</p>
<p>Can scotus decide not to hear inter-state litigation in the same way it often does with constitutional matters or are they forced to mediate because there is no other way to settle such matters?</p>

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<p>As I understand it one of Scotus jobs is to mediate inter-state
litigation. Did this happen with equal regularity over the years or
was this something that happened mainly when the union was new?</p>
</blockquote>
<p>You are right the Supreme Court of the United States is the venue for state vs. state disputes. Though I would be careful to differentiate &quot;inter-state&quot; litigation from &quot;stave vs. state&quot; litigation. These disputes did happen regularly over the years yes, but with differing success as the strength of the Federal Government and Supreme Court increased*. In general state v. state cases are not too common, and generally deal with issues such as land and border disputes or questions.</p>
<p>*(See as a partial reference this video where when NJ sued NY over a land dispute, NY effectively ignored the Court/ the Court didn't hear the case in 1832. Whereas in the 1990s NY did not ignore it <a href="https://www.youtube.com/watch?v=SgZ1f4ACZBQ" rel="noreferrer">https://www.youtube.com/watch?v=SgZ1f4ACZBQ</a>)</p>
<p>For background the relevant provisions of the Constitution and statute are as follow:
U.S. Const. Article III: Sec 2:</p>
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<p>In all cases affecting ambassadors, other public ministers and
consuls, and those in which a <strong>state shall be party</strong>, the Supreme Court
shall have original jurisdiction. In all the other cases before
mentioned, the Supreme Court shall have appellate jurisdiction, both
as to law and fact, with such exceptions, and under such regulations
as the Congress shall make. <a href="https://www.law.cornell.edu/constitution/articleiii" rel="noreferrer">https://www.law.cornell.edu/constitution/articleiii</a></p>
</blockquote>
<p>28 USC Sec. 1251</p>
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<p><strong>(a)The Supreme Court shall have original and exclusive jurisdiction of
all controversies between two or more States.</strong></p>
<p>(b)The Supreme Court shall have original but not exclusive jurisdiction of:
(1)All actions or proceedings to which ambassadors, other public ministers, &gt; consuls, or vice consuls of foreign states are parties;
(2)All controversies between the United States and a State;
(3)All actions or proceedings by a State against the citizens of another State or against aliens. <a href="https://www.law.cornell.edu/uscode/text/28/1251" rel="noreferrer">https://www.law.cornell.edu/uscode/text/28/1251</a></p>
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<p>For a recent/ current state v. state case see Mississippi v. Tennessee: <a href="https://www.supremecourt.gov/docket/docketfiles/html/public/22o143.html" rel="noreferrer">https://www.supremecourt.gov/docket/docketfiles/html/public/22o143.html</a> concerning territorial matters/ water rights.</p>
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<p>Is it therefore at least in theory possible for two states to have
contrary laws and scotus be forced to make a value judgment contrary
to state law to resolve some dispute?</p>
</blockquote>
<p>Generally no, unless the state law is impermissible under the United States Constitution or otherwise preempted by federal law for example. But the Supreme Court wouldn't really rule on &quot;contrary&quot; state laws, most cases are concerning federal laws or land matters. Also, unless there is a matter of Federal Law (&quot;federal question&quot;) or the state v state controversy under Article III the Supreme Court doesn't have jurisdiction to rule on state matters (again unless a &quot;federal question&quot; is involved).</p>
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<p>Can scotus decide not to hear inter-state litigation in the same way
it often does with constitutional matters or are they forced to
mediate because there is no other way to settle such matters?</p>
</blockquote>
<p>Yes, they can choose not to hear state vs. state cases. Rule 17 of the Supreme Court Rules regards &quot;Procedure in Original Action&quot; <a href="https://www.law.cornell.edu/rules/supct/rule_17" rel="noreferrer">https://www.law.cornell.edu/rules/supct/rule_17</a> in which the Court &quot;Court thereafter may grant or deny the motion, set it for oral argument, direct that additional documents be filed, or require that other proceedings be conducted.&quot;</p>
<p>Though, and I will note for completeness in answering your question, some current Justices believe it is not discretionary. See below:</p>
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<p>155, ORIG. TEXAS V. PENNSYLVANIA, ET AL.<br />
The State of Texas’s motion for leave to file a bill of complaint is denied for lack of standing under Article III of the Constitution. Texas has not demonstrated a judicially cognizable interest in the manner in which another State conducts its elections. All other pending motions are dismissed as moot.</p>
<p>Statement of Justice Alito, with whom Justice Thomas joins: In my view, <strong>we do not have discretion to deny the filing of a bill of complaint in a case that falls within our <em>original jurisdiction</em></strong>. See <em>Arizona v. California</em>, 589 U. S. ___ (Feb. 24, 2020) (Thomas, J., dissenting). I would therefore grant the motion to file the bill of complaint but would not grant other relief, and I express no view on any other issue.
<a href="https://www.supremecourt.gov/orders/courtorders/121120zr_p860.pdf" rel="noreferrer">https://www.supremecourt.gov/orders/courtorders/121120zr_p860.pdf</a></p>
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