The killing of two police officers and a paramedic in Burnsville last month has made "straw purchases" of firearms a critical issue for Minnesota lawmakers of both parties.

Rep. Kaela Berg, DFL-Burnsville, said she wanted to craft a bill to address the specific circumstances of those shootings. The gunman was not legally allowed to own firearms, and federal prosecutors said in an indictment that his girlfriend purchased the weapons.

"The AR-15-style weapons that were used against the first responders should not have been in the possession of the assailant," Berg said.

Berg's bill would make it a state felony to buy guns for someone barred from owning them. Under state law, that offense is a gross misdemeanor, though it is already a felony at the federal level. The bill would also outlaw binary triggers, devices that effectively speed up the rate of semiautomatic gunfire. Rep. Kelly Moller, DFL-Shoreview, noted that the gunman who killed a Minnesota-born police officer in Fargo last year also used a binary trigger.

Berg's bill had a hearing in a House committee Thursday, and a Senate committee will hear the bill on Friday.

Republican legislators support stiffer state penalties for someone who makes a straw purchase, but some charge Democrats with delaying a vote on them. Sen. Julia Coleman, R-Waconia, said the Senate bill replicates one she sponsored last year that never made it to the Senate floor.

"This could have passed last year, and Democrats held it up," Coleman said.

In a news conference and an impassioned floor speech on Thursday, Coleman said she "firmly believe[d]" the woman, Ashley Dyrdahl, alleged to have purchased guns for the Burnsville gunman would not have done so, had straw purchasing been a felony under state law. Dyrdahl faces federal charges, including straw buying.

Coleman said Sen. Heather Gustafson, DFL-Vadnais Heights, "told me she would be cloning my bill with the exact same language," adding that Gustafson explained to her that "Republicans can't be the ones to pass this bill."

Gustafson responded in an emailed statement: "Ultimately, I valued the starting point of Senator Coleman's bill," Gustafson wrote, adding, "I believe there is more work to be done." Gustafson said she planned to amend her bill Friday.

In the House, Republicans raised similar concerns, pointing to a bill by Rep. Peggy Scott, R-Andover, that would also have made straw purchases a felony. Berg said it was "likely a mistake on my part" not to reach out to Scott to work together on a bill, but she said she wanted to craft something quickly that dealt with the specific circumstances of the Burnsville shooting after the federal indictment against Dyrdahl was released.

There are key distinctions between the Republican and Democratic bills in the House, Moller said. Namely, the DFL bill makes it a felony to buy guns for someone the purchaser "reasonably should know" is not allowed to possess firearms, while the Republican bill makes it a felony if the purchaser "knows" someone is not allowed to own guns. The DFL bill also requires the Bureau of Criminal Apprehension to produce a report on gun trafficking in Minnesota.

In Thursday's House hearing, GOP legislators said they agree with tougher penalties for straw purchases.

"I am supportive of the straw buyer part of this," said Rep. Jeff Witte, R-Lakeville, a retired Burnsville police officer.

But some House Republicans chafed at the idea of banning binary triggers in the same bill.

"The straw purchaser bill should have been done by itself," said Rep. Matt Grossell, R-Clearbrook. "I don't know why you had to muck it up."

Rep. Paul Novotny, R-Elk River, suggested some wording changes to make sure the binary trigger ban did not inadvertently ban other kinds of semiautomatic firearms. Democrats said they were open to his suggestions.

Correction: An earlier version of this story incorrectly identified the legislator who noted that the gunman in Fargo used a binary trigger. It was Rep. Kelly Moller.