OLYMPIA — Gov. Jay Inslee on Friday signed a proclamation that returns to the Yakama Nation almost all civil and criminal authority over tribal members on its reservation.

Tribal Council Chairman Harry Smiskin said the signing is the first of its kind in the country.

But the deal is not done yet. The proclamation needs federal approval, which Smiskin said will probably take another year or so of working with the government on details, such as financial support for both law enforcement and civil authority over social issues, such as child and family services and school truancy.

The Yakama Nation is a sovereign nation that has the authority to govern itself under a treaty signed in 1855 with the federal government. The tribe has its own police department and jail, and has always had some criminal authority over tribal members.

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In 1953, under Public Law 280, Congress gave states the authority to take more civil and criminal control over Indian lands. In 1963, Washington state asserted governmental jurisdiction over school attendance, domestic relations, mental illness, juvenile delinquency, adoption, public assistance and motor-vehicle operation on tribal lands.

In 2012, the Legislature created a process for tribes to apply to take back that lost authority, and the proclamation is the result of the Yakama Nation’s petition. The Yakama petition, filed in 2012, asked the state to retain authority over mental illness as it arises in the courts, and civil commitment of sexually violent predators, but return the rest of the authority taken in 1963.

The state retains jurisdiction over criminal or civil cases that involve non-Indians, even if a tribal member is also involved.