Portland Mayor Ted Wheeler plans to take a harder line at Wednesday's City Council meeting by asking police to arrest disruptive people if they do not leave when requested, spokesman Michael Cox said.

The mayor's shift in strategy follows months in which protesters shut down and interrupted City Council meetings, preventing commissioners from conducting city business. The mayor has moved or ended council meetings abruptly because of rowdy conduct.

Last week, after a particularly chaotic council meeting, Commissioner Nick Fish directed employees in his office and bureaus to stop attending until he's satisfied it is safe to do so.

Wheeler's failed attempts to quell protesters drew complaints from activists, the American Civil Liberties Union of Oregon and Portland City Hall staffers for different reasons.

They all questioned why the mayor rarely asked disruptive individuals to leave.

One longtime aide in Fish's office said the protesters' behavior triggered his post-traumatic stress disorder, forcing him to retire. Senior Policy Director Jim Blackwood Jr. will retire Saturday after working in Fish's office for more than seven years.

"Two mayors...have been ineffective in making City Hall a safe place," Blackwood said. "They're ultimately responsible."

Blackwood's retirement comes after an activist publicized controversial Facebook posts Blackwood wrote, some of which highlighted black men killing police officers, called the shooting of a protester at an anti-Trump rally "inevitable" and criticized Commissioner Amanda Fritz.

The mayor takes concerns about the protesters' behavior seriously, Cox said.

"It's clear that the abusive, hostile, disruptive behavior has not abated," Cox said. "It's gone in the opposite direction. It's been worse."

Cox said the mayor has asked people to leave council meetings at least twice, cleared the council chambers several times and reconvened in City Hall's Rose Room at least once since the mayor took office in January. Wheeler has tried to avoid expelling citizens because he sees that as escalating the situation, Cox said.

"Our preference is to have council meetings that run according to rules of decorum and procedure, but that's not always everybody's goal," Cox said. "In the end, it is our responsibility."

Portland police officers will be available to make arrests Wednesday, Cox said, but he declined to say how many officers will respond or where they will be stationed.

"The police will make staffing decisions based upon the need," Cox said.

Fish received a security briefing from the mayor on Tuesday. He told The Oregonian/OregonLive that he felt "very encouraged" and that he will allow his bureau and office staffers to attend Wednesday.

"Obviously no one can guarantee there won't be disruptions at council," Fish said. "The question is how do you deal with potential disruptions. I believe the mayor has a thoughtful, well-coordinated plan, and he has my support."

--Jessica Floum

503-221-8306