Protesters who block freeways and people who intentionally help those who damage pipelines or other utilities could face new legal penalties starting this summer.

Lawmakers in the Minnesota House considered two measures Tuesday cracking down on such protests. Opponents called them an attack on the First Amendment, while supporters said they will protect property and public safety.

"It's a way for the Legislature to say, 'This type of behavior is not OK,' " Rep. Nick Zerwas, R-Elk River, said of his proposal to increase the penalty for people who interfere with freeway traffic or block airport roads.

Such behavior is currently illegal, Zerwas said, so his proposal is not impinging on free speech. The measure raises the punishment from a misdemeanor to a gross misdemeanor, which is punishable by a maximum fine of $3,000 or up to a year in jail.

The proposal, which also passed late Tuesday night, comes in response to past marches on Interstates 94 and 35W, as well as on roads near the airport, intended to draw attention to police shootings of black men. Protesters took to the freeways after Minnesota police shot and killed Jamar Clark and Philando Castile in 2015 and 2016.

"What we're doing is obviously chilling speech. That is the intent of the bill," said Ben Feist, the ACLU of Minnesota's legislative director.

Feist said the protests amount to an inconvenience for drivers, and responding with up to a year in jail doesn't make sense. "The punishment does not fit the crime," he said.

But Zerwas noted a police officer was injured during the protest on I-94 when someone dropped a concrete block on his head.

"We can't allow this to continue," he said. "It's just too dangerous."

The other protest-related measure from Rep. Dennis Smith, R-Maple Grove, which passed Tuesday night, comes as people are organizing against oil pipelines like the proposed Enbridge Line 3 replacement in northern Minnesota. His proposal says a person or entity that intentionally "aids, advises, hires, counsels, or conspires" with someone who damaged — or trespassed with the goal of damaging — a pipeline, facility or utility may be held criminally liable.

A letter to House members opposing the measure said it unjustifiably imposes prison sentences and financial liabilities on people deemed to be "guilty by association."

"This legislation unfairly targets Minnesotans who choose to express themselves and peacefully assemble on certain, selectively chosen matters of public policy, and would put Minnesota in the national spotlight for criminalizing freedom of expression," said the letter, which was signed by 44 groups, including the local chapter of the Sierra Club and Minnesota Nurses Association.

If the Senate and Gov. Mark Dayton agree to the two measures, they would take effect Aug. 1. Dayton has previously said he would be open to increased penalties on protesters who block freeways.