Michigan lawmakers approved several measures Thursday and early Friday that critics say will make it much more difficult for voters to make their voices heard.

The measures passed amid a flurry of activity in the GOP-controlled legislature during a lame-duck session before Democrats take control of the governor’s mansion. It’s unclear if outgoing Gov. Rick Snyder (R) will sign the bills into law.

One of the bills makes it more difficult for voters to place a referendum on the statewide ballot. Currently, Michiganders can place a measure on the ballot as long as they clear a minimum number of signatures. The new measure, which came up for a vote at 6 a.m. Friday, says organizers can get no more than 15 percent of their signatures from any one of the state’s 14 congressional districts, a move that limits the voices of voters in more populated and liberal-leaning areas of the state. The measure also comes after Michigan voters approved ballot measures to legalize recreational marijuana, limit partisan gerrymandering and make it easier to vote.

“It without question will make the process more expensive and more difficult,” said Sharon Dolente, a voting rights strategist at the ACLU of Michigan. “I don’t think there’s any other way to understand it other than undermining the very successful efforts of citizens this year to pass these reforms.”

Lawmakers justified the 15 percent cap by saying that it would ensure there was broad support for initiatives that made it onto the ballot. But both liberal and conservative advocacy groups opposed the bill, saying that there shouldn’t be restrictions on how voters could express their political beliefs.

It without question will make the process more expensive and more difficult. I don’t think there’s any other way to understand it other than undermining the very successful efforts of citizens this year to pass these reforms. Sharon Dolente, a voting rights strategist at the ACLU of Michigan.

Dolente disputed the lawmakers’ justification and their claim that activists currently did not need to get broad support for a measure to get it on the ballot. Organizers already have to gather hundreds of thousands of signatures to qualify.

“It’s based on a premise that’s not even true. Nobody can collect all the signatures in Lansing, Grand Rapids and Detroit,” Dolente said. “I don’t know where that logic ends. Do I need to have everyone in every city or township in the state?”

Republicans also passed a set of measures, which tweaks the constitutional amendment voters enacted in November that made it easier to vote in Michigan. The amendment voters passed has a host of voting changes, including allowing people to vote absentee with no excuse, requiring the state to automatically register voters when they interact with state agencies and allowing people to register to vote on election day. The bill lawmakers passed, however, says that anyone who registers to vote within 14 days of an election ― a time when registration typically surges ― can only do so in person at the clerk’s office in the city or township where they live.

The bill also requires people who register during this period to present proof of residency, which can be a driver’s license, state ID card, utility bill, bank statement, paycheck or government document.

Dolente of the ACLU, which backed the amendment, said restricting registration to a single clerk’s office might overwhelm election officials and would put another obstacle in front of new voters.

“Some townships are very very large. Detroit, the distance that some voters might live from the clerk’s office might be 20 minutes by car. Michigan is notorious, particularly the Metro Detroit area for having a very weak transit system,” she said.

Dolente also said the legislature shouldn’t be limiting a constitutional amendment voters overwhelmingly approved.

“It’s not really for the legislature to tinker with this,” she said. “If they wanted to have a say, then they should have moved these things and not let Michigan languish to be sort of the bottom of the barrel in terms of states and access.”

Lawmakers were also considering tweaking the amendment voters passed to set up an independent redistricting commission, but that legislation died during the lame-duck session.