From the Colorado Attorney General’s office via the Valley Courier:
[On Monday, January 8, 2018], Colorado Attorney General Cynthia H. Coffman’s office presented arguments in the U.S. Supreme Court in Texas v. New Mexico and Colorado, No. 141, Original, to protect the authority and jurisdiction of the Western States to manage water rights within their own borders and across state lines in cooperation with neighboring state officials.
The case reached the U.S. Supreme Court after Texas sued New Mexico over a dispute regarding water in the Rio Grande Basin. Colorado, Texas and New Mexico are all parties to the Rio Grande Compact, an agreement that since 1938 has regulated the interstate apportionment of the waters of the Rio Grande. Texas did not make any claims against Colorado, but because Colorado is a party to the Compact, Colorado was also included in the case.
While Texas’s claims against New Mexico were pending, the U.S. government attempted to independently sue the State of New Mexico under the Rio Grande Compact. The Supreme Court invited the State of Colorado to present arguments on whether the United States has a right to sue a State under an interstate water compact, despite not being a party to it.
“Arguments over water rights have been going on since the beginning of statehood, but the authority to manage this critically important natural resource has always belonged first and foremost to the States,” said Attorney General Coffman. “We cannot allow the federal government to encroach on our rights and interfere with our ability to manage water resources on equal footing with our Sister States.”
Colorado Solicitor General Fred Yarger argued on behalf of the State, explaining that the federal government does not have a right to sue New Mexico under the Rio Grande Compact. The United States is not a party to the Compact, he explained, and the authority, jurisdiction and responsibility to manage the water of the Rio Grande lies with the States. Solicitor General Yarger argued that allowing the federal government to sue under the Compact to which it is not a party would set a very concerning precedent, harming the ability of States to work together to solve water disputes cooperatively, without federal government intrusion.