Nik Rajkovic / news@whmi.com

The Michigan Court of Appeals will decide the Mackinac Center for Public Policy’s lawsuit challenging the wrongfully increased income tax rate by March 11, according to the Michigan Supreme Court.

The Mackinac Center is fighting the Michigan Department of Treasury’s decision to raise the personal income tax rate back to 4.25% in 2024. It was lowered to 4.05% last year due to a 2015 law that created a tax cut trigger, which automatically lowers taxes when state revenue outpaces inflation by a set amount.

The Mackinac Center argues state wrongly asserts that the phrase 'current rate' in the law means any income tax reduction would only be for one year.

The group claims the tax hike is costing Michigan taxpayers an additional $714 million a year.

"This announcement from the Michigan Supreme Court is a significant step toward clarity for Michigan’s 4.9 million taxpayers," said Patrick J. Wright, vice president for legal affairs at the Mackinac Center.

"This illegal tax hike costs taxpayers an additional $714 million a year. The Legislature meant to give permanent tax relief when the state's revenues got extremely high. We hope the courts will agree and recognize the permanence of any tax cuts under this statute."