| Dec 18 2014 | Motion for leave to file a bill of complaint filed. |
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| Feb 10 2015 | Order extending time to file response to the bill of complaint to and including March 27, 2015 |
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| Feb 19 2015 | Brief amici curiae of All Nine Former Administrators of Drug Enforcement filed. |
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| Mar 27 2015 | Brief amicus curiae of Washington and Oregon filed. |
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| Mar 27 2015 | Brief of respondent Colorado in opposition filed. |
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| Apr 03 2015 | Reply of plaintiffs Nebraska and Oklahoma filed. |
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| Apr 15 2015 | DISTRIBUTED for Conference of May 1, 2015. |
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| May 04 2015 | The Solicitor General is invited to file a brief in this case expressing the views of the United States. |
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| Dec 16 2015 | Brief amicus curiae of United States filed. |
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| Jan 05 2016 | Supplemental brief of petitioners Nebraska and Oklahoma filed. (Distributed) |
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| Jan 06 2016 | DISTRIBUTED for Conference of January 22, 2016. |
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| Feb 08 2016 | DISTRIBUTED for Conference of February 19, 2016. |
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| Feb 29 2016 | DISTRIBUTED for Conference of March 4, 2016. |
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| Mar 14 2016 | DISTRIBUTED for Conference of March 18, 2016. |
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| Mar 21 2016 | Motion for leave to file a bill of complaint DENIED. Justice Thomas with whom Justice Alito joins, dissenting from the denial of motion for leave to file complaint. (Detached Opinion) |
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