16 U.S. Code § 163 - Jurisdiction by the United States; fugitives from justice
Sole and exclusive jurisdiction is assumed by the United States over the territory embraced within the Glacier National Park, saving, however, to the State of Montana the right to serve civil or criminal process within the limits of the aforesaid park in suits or prosecution for or on account of rights acquired, obligations incurred, or crimes committed in said State but outside of said park, and saving, further, to the said State the right to tax persons and corporations, their franchises and property, on the lands included in said park. All the laws applicable to places under the sole and exclusive jurisdiction of the United States shall have force and effect in said park. All fugitives from justice taking refuge in said park shall be subject to the same laws as refugees from justice found in the State of Montana.
A provision accepting the act of the Montana Legislature which ceded to the United States Exclusive Jurisdiction over the Territory referred to in this section has been omitted as executed.