Lansing — Legislative Republicans violated the Michigan Constitution last year when they adopted and then weakened minimum wage and paid sick leave initiatives, Democratic Gov. Gretchen Whitmer argued Wednesday in a new court filing.

Whitmer had not yet taken office when the GOP-led Legislature used the unprecedented adopt-and-amend strategy, but the Michigan Supreme Court is asking supporters and opponents alike to weigh in as justices consider whether to issue an advisory opinion on its legality.

Mark Totten, the governor’s chief legal counsel, echoed arguments by Democratic Attorney General Dana Nessel and other critics as he urged the court to “ensure this scheme is never used again" to undermine citizen-led petition drives.

“One thing, however, cannot be stressed enough: The violence this ‘adopt and amend’ maneuver does to the core constitutional values of this state and the democratic dignity of its people,” Totten wrote in the Whitmer brief.

Republicans have defended the lame-duck move to adopt and then significantly change the minimum wage and paid sick leave laws before they took effect. The proposals would have otherwise gone to the November ballot for voters to decide.

GOP leaders in February asked the Michigan Supreme Court to issue an advisory opinion in an attempt to stave off potential lawsuits.

At issue is whether lawmakers can adopt and amend citizen-initiated legislation in the same two-year session. The Republican-led Legislature did so last year after Republican then-Attorney General Bill Schuette gave his legal blessing.

Attorneys for a group called the Counsel for Small Business for a Better Michigan Coalition argued last month in support of the legislative maneuver.

“The Constitution does not prohibit the Legislature from amending an initiated law that it enacted during the same session, so the Legislature has plenary power to do so,” wrote attorneys Gary Gordon and Jason Hanselman.

The Supreme Court is not obligated to issue an advisory opinion, but the small business group urged justices to do so to “bring certainty to employers and employees seeking to enter into and continue existing employer–employee relationships.”

Schuette had reversed a 1964 legal opinion from Democratic former Attorney General Frank Kelly, who said adopting and amending an initiative in the same session would violate the “the spirit and letter” of the initiative process.

The Supreme Court required Nessel’s office to file briefs arguing both for and against the constitutionality of the law.

Organizers collected hundreds of thousands of petition signatures to send the paid sick leave and minimum wage proposals to the Legislature, which has constitutional authority to adopt initiatives within 40 days or allow them to go to the ballot.

"With its “adopt and amend” maneuver, the 2017-2018 Legislature both gutted this initiative process and validated the popular distrust that drove its creation," Totten argued in the Wednesday filing. "Nothing exceptional provoked this."

Under the amended minimum wage law, Michigan’s base rate will increase from $9.25 to $12.05 per hour by 2030, slowing the march to $12 by 2022 called for in the initiative. The minimum wage for tipped restaurant workers will rise to $4.58 by 2030 instead of $12 by 2024.

The paid sick leave law will exempt more than 160,000 small businesses that collectively employ more than 1 million workers from a mandate that would have otherwise applied to every company in the state.

“Michiganders turned out in historic numbers to get minimum wage and paid sick leave on the ballot, and we need to respect their wishes,” Whitmer said in a statement after submitting her filing.

“Every person should be able to trust that their elected officials have their best interests in mind, which is why we must end the unconstitutional games that the Legislature has been playing with voters. Today’s filing gets us one step closer to restoring the public’s trust in state government.”

joosting@detroitnews.com