Kansas Act of 1940

The Kansas Act of 1940 addressed the means by which Congress could use its power under the Indian Commerce Clause to authorize a state's ability to exercise jurisdiction in certain instances. Because the inherent sovereignty of Indian nations generally precluded state jurisdiction over Indian country, the Act became one of the first legislative actions to permit state jurisdiction over most offenses committed by or against Indians on Indian reservations. This was a departure from previous federal policy in which the Federal Government had sole jurisdiction over Indians. The Act was a precursor to the Indian termination policy and in essence was a kind of "trial legislation" to see if such transfers would be effective. Several other states followed suit. Today, the jurisdictional gap which existed when the Kansas Act was passed no longer exists, and instead there is an overlap; a native person committing a single crime within Indian country in the state of Kansas could be prosecuted by the United States, the State of Kansas, and one of the tribes.

In March 1938, Potawatomi Agency Superintendent Bruce contacted federal legislators from Kansas and proposed a bill for Kansas to obtain jurisdiction over criminal cases on Indian lands in Kansas. There was a perception, that because at that time, none of the four tribes —- Potawatomi, Kickapoo, Sac & Fox, Iowa —- had tribal courts to deal with offenses, lawlessness would prevail if the state were not allowed jurisdiction over crimes that were not federal offenses. In addition, because of the allotment program, approximately 80,000 acres of Indian land had been assigned to tribal members and were in state jurisdiction, while only about 35,000 acres of Indian land were held in the federal trust.

Bruce cited 6 reasons the Federal Government might support the transfer:

Up until this time, Kansas had exercised jurisdiction over offenses, including those listed in the Indian Major Crimes Act, but when that authority was called into question, the state sought clarification of its authority. Accordingly, the stated purpose of the act was to “merely confirm a relationship which the State has willingly assumed, which the Indians have willingly accepted, and which has produced successful results, over a considerable period of years.” H. R. Rep., at 5; S. Rep., at 5.4

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