A class-action lawsuit has been filed against the city of Phoenix and police Chief Jeri Williams, claiming her officers violated the rights of thousands of people who were protesting outside President Donald Trump's August 2017 downtown rally.

The lawsuit, filed in U.S. District Court in Phoenix on behalf of activist groups Puente Arizona and Poder in Action, and four named residents, claims police used excessive force while dispersing crowds outside of the Phoenix Convention Center on Aug. 22, 2017.

Officers fired more than 590 projectiles "indiscriminately" into a crowd that "included children, elderly people, disabled people, and pregnant women," the lawsuit said.

"Under the direction of Chief Williams, Phoenix police disregarded the constitutional rights of protesters that night," said ACLU of Arizona Legal Director Kathy Brody in a statement.

MORE: We could communicate better, Phoenix police say in report on Trump protest

"At the precise moment when anti-Trump protesters intended to deliver to the president and his supporters their messages renouncing his policies, Phoenix police — without warning — used incapacitating weaponry to silence and disperse hundreds of peaceful anti-Trump protesters."

The lawsuit was filed by the Arizona chapter of the ACLU, Los Angeles-based law firm Hadsell Stormer & Renick LLP and civil rights attorney Dan Pochoda. Plaintiffs are requesting a court bar Phoenix police from using excessive force against protesters in the future and are also seeking financial rewards.

The ACLU also sued the department last year in a bid to collect public records on the agency's use of force during the rally.

Among those listed as plaintiffs in the lawsuit is Ira Yedlin, a 70-year-old man from Bisbee who traveled to protest Trump. Speaking to The Arizona Republic in the days after the protest, Yedlin said he was a lifelong protester, but what happened as crowds dispersed from the Phoenix rally was unlike anything he had witnessed before.

"I've been at, over the last 50 years, dozens of protests," he said previously. "Never have I seen a police reaction like that without any apparent provocation."

MORE: Arizona protester, 70, says his injuries show police could have done better

Yedlin's version off accounts — and the lack of audible warnings to disperse — became the subject of multiple city hearings and police department reviews.

A Phoenix police internal investigation found officers could have better communicated with protesters, and Williams said she accepted the community criticism that followed the event.

Still, she largely stood by her officers' actions.

"The tragedies that happened in other cities did not happen in Phoenix," she said, referring to the deadly demonstrations in Charlottesville, Virginia, that occurred just days before Trump's appearance in Phoenix.

A 31-page report issued earlier this year provided a harsher self-assessment than the police department had offered in the past. It detailed the ammunition used against the crowd, as well as a timeline of events.

In a section titled "Opportunities for Improvement," the report's suggestions include a "proactive notification process" to communicate with groups causing disorder, greater use of social media and tools — like megaphones — to keep the public informed in real time, and to provide warnings in both English and Spanish.

Key to the report is a 17-minute gap between the time Phoenix police began deploying their munitions — first smoke, then pepper balls, then tear gas — and the first time the agency made widespread warnings to disperse.

At 8:34 p.m., police donned gas masks and requested an air unit to illuminate the area and make announcements to disperse. Police officials initially said the gas masks alone should have been a warning to protesters, a point protesters later would criticize.

The report also shows there was a lag in the time the Air Unit was given instructions to warn protesters and when the announcement was actually made. The report's authors attribute the delay to waiting for clearance from the Federal Aviation Administration. Officers began using their weapons at 8:35 p.m., and the Air Unit announcements kicked out at 8:52 p.m.

None of the officers involved were disciplined.

According to the report, one officer deployed a smoke grenade and two tear gas grenades without receiving direction from the field commander. When asked why he was not disciplined, a Phoenix police spokesman said the officer was certified to use the equipment and was responding to a dynamic situation.

Citing the continuing litigation, a Phoenix police spokeswoman declined to comment Tuesday.

Activist groups have continued to reel from the use-of-force incident, something that has had a chilling effect on subsequent demonstrations in the past 13 months, attorneys said.

"Absent the court’s intervention, those who wish to gather and speak will continue to experience understandable fear of police retaliation when participating in protests, demonstrations, and marches, particularly when expressing anti-Trump views," attorneys wrote.

The 47-page lawsuit also called attention to the surge in police shootings across Phoenix this year. There have been 37 police shootings this year, an unprecedented record that translates, on average, to one incident each week. There were 21 shootings in all of 2017, 25 in 2016 and 17 in 2015.

The city surpassed its annual record of 31 shootings set in 2013 this past July.

“The Phoenix Police Department’s epidemic of violence is a crisis in our community,” Viri Hernandez, executive director of Phoenix-based Poder in Action, wrote in a statement. “The police violence we saw at the anti-Trump protest is the same police violence that has caused Phoenix to lead the nation in officer-involved shootings. The lack of accountability for police violence by the mayor, city council, and Chief Williams is inexcusable.”

Reach the reporter at 602-444-8515, jpohl@azcentral.com or on Twitter: @pohl_jason

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