Authorities in Portland, Ore., are calling for a series of laws to curb violent clashes at demonstrations that include prohibiting masks worn by protesters, allowing police to videotape demonstrations and giving the city greater control over events organized by groups with violent histories.

“We cannot allow people to continue to use the guise of free speech to commit a crime,’’ police Chief Danielle Outlaw said in a Wednesday news conference addressing last week's violence that occurred when three competing demonstrations converged downtown.

“We cannot allow people to continue to use the guise of free speech to commit a crime.’’ — Chief Danielle Outlaw, Portland, Ore., police

Several people were injured in connection with demonstrations as marchers with an anti-fascist group clashed with conservative protesters with the Proud Boys and supporters of the #HimToo movement. Conservative writer Andy Ngo was assaulted by Antifa members and spent the night in an emergency room.

ANTIFA, FAR-RIGHT GROUPS CLASH OUTSIDE PORTLAND BAR AFTER 'PEACEFUL' MAY DAY PROTEST

About 15 states and some countries have anti-mask laws, the Oregonian reported. Opponents argue such laws would deprive people anonymity to express their views and would violate their First Amendment rights.

“We looked into it previously and the constitutional free speech issues are difficult to overcome, at least in Oregon, said Tim Crail, chief of staff for Portland Commissioner Amanda Fritz.

Outlaw said the issue was a matter of public safety. Portland has been the site of several violent demonstrations between Antifa supporters and conservative demonstrators in recent months.

Ngo, who covered Antifa for the website Quillette, was kicked in the head and had objects thrown at him.

“A lot of people are emboldened because they know they can’t be identified,’’ Outlaw said.

“A lot of people are emboldened because they know they can’t be identified.’’ — Chief Danielle Outlaw, Portland, Ore., police

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The American Civil Liberties Union of Oregon said it doubts a policy prohibiting masks could be enforced in a constitutional manner.

"A policy that prohibits wearing a mask to a protest will have police focusing on the wrong issue," Sarah Armstrong, a spokeswoman for the group, told the paper. "Behavior is the issue, not the mask,'' she said. "It could be argued that the mask is an important symbolic part of a protester’s message. ... There are many legitimate reasons people wear ‘masks,’ including political and religious reasons.''