A "We Miss You All! Stay Strong & Stay Safe" sign hangs on a fence at Ramona Elementary School in Alhambra, California on April 28, 2020 as schools across the state remain closed due to the novel coronavirus pandemic. (FREDERIC J. BROWN / AFP)

Public school districts throughout the United States－including in New York, Chicago, Phoenix, Denver, Seattle, Portland, Oregon, and Oakland, California－have either canceled or plan to cancel contracts with police departments to guard their schools.

The cancellations have been prompted by the Minneapolis school board's unanimous vote to end its contract with the city's police department about a week after demonstrations that followed George Floyd's death on May 25

The cancellations have been prompted by the Minneapolis school board's unanimous vote to end its contract with the city's police department about a week after demonstrations that followed George Floyd's death on May 25.

Some have long advocated that police officers should be removed from US public schools, arguing that they pose a greater risk to minority students than the mass killers they are intended to guard against.

"We must take all actions within our power to stop systems of oppression," Kim Ellison, chairwoman of the Minneapolis Board of Education, said in a statement. "For the Minneapolis Public School Board, that means discontinuing our contractual relationship with the Minneapolis Police Department."

The police department quietly stepped aside.

"The Minneapolis Police Department appreciated the opportunity to provide years of service to the Minneapolis Public Schools through the School Resource Officer program," Deputy Chief of Investigations Erick Fors said in a statement.

"We will continue to work in cooperation with the Minneapolis Public Schools regarding safety and security issues."

'Bold move'

Judith Browne Dianis, executive director of the Advancement Project National office in Washington, said in a statement: "Research and the experiences of young people of color have taught us that the police in schools create a toxic school climate and fuel the school-to-prison pipeline.

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"This move by the Minneapolis Public Schools is bold, big and gets us one step closer to re-imagining justice for our young people of color."

About 30 percent of US public primary schools and 70 percent of public secondary schools employ armed law enforcement officers, according to 2016-17 data compiled by the National Center for Education Statistics.

That means there are about 20,000 armed officers in US schools, the National School Resource Officers Association in Hoover, Alabama, said.

But the exact number isn't known because the officers aren't required to register with a national database, and local police aren't required to disclose how many officers are assigned to schools.

The number of officers at schools grew rapidly following the 1999 shooting at Columbine High School in Colorado that left 15 dead, then the worst school shooting in the US.

The Justice Department devoted millions of dollars to fund police at schools to thwart outside threats and to curb crime among students.

Efforts to increase the police presence at schools intensified after the 2018 shooting at Marjory Stoneman Douglas High School in Florida, where 17 people died.

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But critics argue that the increased police presence in schools takes money away from needed educational and social programs.

The American Civil Liberties Union, a New York-based nonprofit organization founded in 1920 to defend individual rights, reviewed data compiled by the US government and found that 1.7 million students are enrolled in schools that employ law enforcement officers, but not guidance counselors.