"It doesn't make any sense for police brutality to continue and nothing to be done about it," the victim's grandmother, Renee Hankerson, said.
Eyewitness News broke the story last week after obtaining video tape showing Rettrey sitting outside his apartment building waiting for a friend. He was approached by an officer, searched and, after a few words were exchanged, punched by the officer. Three other Newark cops jump in also.
"It's awful, God awful," Newark Mayor Cory Booker said. "And what we did was move aggressively, took a severe step and severed with an employee, without pay."
"Stop police brutality! Stop police brutality! In the black community! In the black community!" the protesters chanted.
But African-American leaders say the disciplinary action against the officers is just a just a first step.
"We are calling on the city of Newark to do something that is 43 years overdue," said Zayid Muhammed, of the New Black Panthers Party. "Create an independent monitor that oversees police behavior and has the power to prosecute."
About 50 people attended the rally on the Spruce Street steps, where the incident took place, and marched down to the steps of City Hall for another rally.
"I just want to make sure we get some results, that's all," Tenants Association president Latrice Smith Quinones said. "I just want to make sure everything is done correctly."
And the very agency being protested was out in full force, on motorcycles, horseback and foot, to videotape and monitor the protest.
"I don't understand why every time the community wants to assemble in a peaceful manner, there's an overwhelming number of officers," protester Lynda Lloyd said.