Baltimore police Officer Edward Nero has been found not guilty of all four misdemeanor charges he faced in connection with the arrest of Freddie Gray.

Gray died on April 19, 2015, after suffering injuries while in police custody.

Following the ruling, Baltimore Mayor Stephanie Rawlings-Blake said in a statement, "This is our American system of justice and police officers must be afforded the same justice system as every other citizen in the city, state, and country."

Outside the courthouse, about a dozen protesters gathered. Once news of the verdict made its way through the crowd, they began chanting, "Indict, convict, send those killer cops to jail!"

The Rev. Westley West, a well-known activist in Baltimore, looked shocked. He was angry.

"[Baltimore] should be upset," he said. "They should also let their voice be heard. Take to the streets. How much longer are we gonna lay down and let the same thing to keep happening?"

Nero was not charged directly with Gray's death. As the Two-Way reported when the bench trial began, he faced charges of second-degree assault, misconduct in office and reckless endangerment.

Nero, 30, was accused of negligence for failing to buckle Gray into a seat in the police van. Gray's neck was broken during transport while he was handcuffed and shackled, but not buckled in.

One unconventional element of the case against Nero has drawn attention: Nero was accused of assaulting Gray, 25, by arresting him without probable cause. "Nero's defense has said they can find no other case of an officer being prosecuted like that," NPR's Jennifer Ludden reported earlier this month.

Multiple police officers face charges in connection with Gray's death, including charges of manslaughter and murder.

Nero is the second of the officers to be brought to court; the first trial, of Officer William Porter, ended in a hung jury.

As Nero left the courthouse, the group of protesters followed him. Tina Thompson, 29, screamed that he should be ashamed.

As he entered a parking garage, with other officers surrounding him, Thompson was overcome with emotion. She doubled over near the sidewalk. She said she felt like throwing up. She cried.

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