President Donald Trump makes an address to Arizona supporters Wednesday in a Phoenix rally expected to draw an estimated 20,000 people. While a great many of them come to show support for his reelection campaign, others schedule protests.

The last Trump rally in the city ended with police intervention. Peaceful protests escalated when a small group began throwing water bottles and attacking a barricade. Police reacted swiftly, firing tear gas to disperse the crowd of protesters. In total, they fired almost 500 pepper spray balls, 16 tear gas canisters, and 71 beanbags, flashbang grenades, or smoke bombs.

In one incident, a protestor kicked a tear gas can away from fellow protestors. Police responded by firing rubber bullets at him. One struck him in the groin. Following the protest, the injured man discovered police mockery online. Subsequently, he filed a lawsuit against the Phoenix police department for excessive force and cruel and unusual punishment.

His isn’t the only lawsuit from the previous Trump rally. Another, filed by the ACLU, collects a class action against the Phoenix PD and City of Phoenix. They argue the police used excessive force to disperse the crowd. They also state officers failed to announce the protest became unlawful. Their lawsuit also states officers fired indiscriminately into the crowd without warning.

Trump Rally Precautions

This time around, presumably to dodge claims of inadequate announcements, Phoenix police acquired Long Range Acoustic Devices. They blast an officer’s voice up to 154 decibels, capable of causing acute hearing loss.

At today’s rally, Secret Service officials will secure Veterans Memorial Coliseum, while local law enforcement secures the surrounding area. Protesters plan to demonstrate throughout the day, including a mile and a half march from Puente Arizona’s headquarters near Adams Street and North 20th Avenue to the coliseum.

Police gave advance warning assemblies may be declared unlawful.