Chicago courts and police are bracing for potential mass arrests ahead of the Democratic National Convention in a city that has seen brutal images of officers beating protesters during the tumultuous events of 1968 before this year’s conference.

Court officials announced that a closed courtroom at the Chicago Police Department will be temporarily opened to question and release dozens of people if necessary.

The Chicago Police Department — which has paid millions of taxpayer dollars to defend itself and settle lawsuits related to misconduct during the 2020 protests — has also pledged to respect the civil rights of protesters and prepared for the riots by holding live drills with actors playing the roles of screaming protesters.

But civil rights groups and the city’s police watchdog expressed “serious concerns” about the “mass arrest” policy and the ability of law enforcement to responsibly deal with potentially thousands of people marching in the streets and near the United Center, where the convention will be held.

Dozens of groups plan to protest Democrats’ support for Israel’s war in Gaza during the convention.

“Police should seek to de-escalate contact with protesters and cannot use interactions as a pretext for mass arrests, violence or retaliation,” Edwin C. Yohnka, communications and public policy director for the ACLU of Illinois, said last week in response to plans to establish a security perimeter at the event.

“Merely engaging in First Amendment activities, including peaceful activities that may cause inconvenience to others, is never grounds for arrest. Arrests should not be used to suppress free speech,” he added.

The convention will return to the Windy City the week of Aug. 19, when Vice President Kamala Harris is expected to be formally designated as the party’s nominee to face Donald Trump in the 2024 election.

Threats of political violence and ongoing demonstrations against U.S. support for Israel’s war in Gaza have loomed over this year’s election. Secret Service personnel are also expected to face heavy scrutiny following the attempted assassination attempt on Trump during a rally in Pennsylvania on July 13. The law enforcement failures prompted officials to call for the resignation of agency director Kimberly Cheatle, who resigned last week.

Cook County judges have scrambled to clear their civil and criminal trial calendars, and Chicago jurors won’t be summoned to one of Illinois’ busiest courthouses this week.

The courtroom at the Area 3 police station at Belmont and Western avenues in the city’s northwest end will reopen to handle “coordinated multiple arrests” — situations in which an officer transfers a person in custody to another officer so the first officer can remain on the scene. It will be open from 8 a.m. to midnight to help process defendants quickly.

From there, they will be released from the station with a ticket or detained for questioning before a judge. The station can accommodate about 90 people at a time, according to officials.

The state’s Pretrial Fairness Act mandates a presumption of release, and the charges most likely to be brought against protesters are not eligible for pretrial detention. Most people arrested during a mass event, if any, are likely to be released the same day.

At least 57 judges have received training on the Pretrial Integrity Act and will hear cases at the same centre if necessary, according to a court spokesman.

“We want to make sure that the police can focus on keeping people safe and that the rights of those arrested are scrupulously respected,” Cook County Chief Judge Evans said last week.

Police Superintendent Larry Snelling said the city police have learned from past mistakes and are preparing for the best while bracing for the worst.

“We will respond to protect people’s rights. We will respond to protect the city,” he said earlier this month. “And we want to make sure we keep it as peaceful as possible.”

A coalition of civil rights and community organizations warned that an early draft of the “mass arrest” policy “undermines protections” for protesters. After it was rewritten, the group continued to express “serious concerns,” according to federal court documents.

The group argued that the policy does not distinguish between First Amendment-protected activities and unlawful activities such as looting, nor “between unlawful but nonviolent civil disobedience and unlawful activities that may result in physical harm to persons or property.”