The Supreme Court ruled Monday that Indian tribes have the authority to prosecute members of other tribes for crimes committed on their reservations. And because tribes act as sovereign nations in such prosecutions, the court said, ordinary principles of double jeopardy do not apply and do not bar the federal government from bringing a subsequent prosecution for the same offense.
The 7-to-2 decision was welcomed by Indian tribes, which in a 1990 Supreme Court decision lost the authority to enforce their criminal laws against members of other tribes. Congress promptly amended the Indian Civil Rights Act to restore that power. The case on Monday required the Supreme Court to decide both the nature and the validity of the Congressional action.
Indian law is complex, and the answers to these questions were not obvious. The practical implications were evident, however. Under a doctrine devised by the Supreme Court in 1922, the constitutional protection against double jeopardy does not apply to consecutive prosecutions by "separate sovereigns" — typically, a state prosecution followed by a federal prosecution, or vice versa.
Under Supreme Court precedent, tribes lack power to prosecute non-Indians. Precedent also makes clear that a tribe exercises its sovereign authority when it prosecutes its own members, and that double jeopardy therefore does not apply. The question in the new case was whether, in exercising its restored authority to prosecute nonmembers, a tribe continues to act as a sovereign.
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