LANSING, Mich. (Michigan News Source) – The Michigan attorney general’s office said the state prosecution of former Gov. Rick Snyder and other officials for their alleged roles in the Flint water scandal have ended.

On Tuesday, the Michigan Supreme Court declined to hear appeals of a lower court’s dismissal of misdemeanor charges against Snyder “effectively closes the door on the criminal prosecutions of the government officials,” prosecutors said in a press release.

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Dana Nessel’s office has zealously pursued the charges, even side-stepping lower court rulings in order to keep the cases alive.

The Michigan Supreme Court in September rejected a last-chance effort by prosecutors to revive criminal charges. The attorney general’s office used a one-judge grand jury to hear evidence and return indictments against nine people. However, the Michigan Supreme Court ruled that process unconstitutional last year.

Snyder was charged with willful neglect of duty. The indictment against him also was dismissed.

Managers appointed by Snyder turned the Flint River into a source for Flint water in 2014, but the water wasn’t treated to reduce its corrosive impact on old pipes. As a result, lead contaminated the system for 18 months. Some experts have attributed a fatal Legionnaires’ disease outbreak in 2014-15 to the water switch.

Flint was reconnected to a regional water system in 2015 and has been compliant with lead standards for seven years, regulators said. The city has replaced most of those lead service lines.

The prosecution team said it expects to release “a full and thorough report” next year which details its efforts and decisions.

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Separately, Michigan taxpayers are on the hook for $600 million as part of a $626 million settlement with Flint residents and property owners who were harmed by lead-tainted water.