In Baldwin et al. v. Fish and Game Commission of Montana et al., the U.S Supreme Court upheld a Montana law that charged higher fees for out-of-state hunters than in-state residents, ruling it did not violate the Privileges and Immunities Clause of the Constitution. The plaintiffs, non-residents who wished to hunt elk in Montana, argued that they were being discriminated against by having to pay more for hunting licenses than residents of the state. However, the court ruled 6-3 in favor of Montana's right to charge non-residents more due to their lack of contribution towards conservation efforts within the state through taxes or other means as compared with local citizens.

In the dissenting opinion for Baldwin et al. v. Fish and Game Commission of Montana, Justice Brennan disagreed with the majority's ruling that nonresident hunters could be charged higher fees than resident hunters for elk hunting licenses in Montana. He argued that this violated the Privileges and Immunities Clause of Article IV, which guarantees citizens of each state equal access to all privileges and immunities in every other state. Brennan contended that hunting was a privilege protected by this clause because it had significant economic implications due to its commercial nature as an industry involving outfitters, guides, equipment suppliers etc., thus making it more than just a recreational activity. Furthermore, he believed there was no substantial reason for discriminating against nonresidents since they did not impose any greater burden on game resources compared to residents; hence such discrimination failed to pass constitutional muster under strict scrutiny analysis applied in cases involving fundamental rights or suspect classifications.