OAKLAND (CBS SF) — Sahleem Tindle’s family left the Alameda County Superior Court disappointed and frustrated on Monday after District Attorney Nancy O’Malley failed to answer a majority of their questions about the 28-year-old man’s death.

BART police officer Joseph Mateu shot Tindle three times in the back, killing him at the West Oakland BART station on Jan. 3.

Police initially said he had a gun in his hand, but later released body camera footage that failed to prove their claim.

Yolanda Banks Reed, Tindle’s mother, said the Alameda County District Attorney’s office tried to cancel Monday’s meeting. “You can change your appointment, but you can’t change mine,” she said.

Before the meeting began, Reed felt “hope and harmony” when she saw signs on the freeway in solidarity with Tindle.

Eight family members were allowed into O’Malley’s office and a group of about 60 supporters chanted and rallied on the second floor of the Alameda County Courthouse.

They proudly shouted “Haki Kwa Mkuu Sahleem,” meaning “Prince Sahleem” in Hebrew, and grew louder as people called for the arrest and firing of Mateu.

Rukiyah Manfield, Tindle’s 18-year-old niece, led a crowd that included several adults and small children wearing white knitted yarmulkes.

When the family emerged, the group formed a circle around Reed and Crystal Hamilton, Tindle’s cousin.

Hamilton said the meeting was unproductive, disappointing and unsympathetic.

O’Malley answered almost all of their questions with “no comment,” according to Hamilton, and did not give clear answers to several others.

They asked her about “countless killings” by police officers, whether Mateu’s use of force was justified, Mateu’s potential promotion within the department and issues of jurisdiction. O’Malley answered several of the questions by saying the shooting was still under investigation.

Hamilton also said the family was not given access to the incident report of Tindle’s shooting.

“Everyone keeps saying he’s in a better place,” Reed said outside the courthouse after the meeting. “What place is this?” She also spoke about Stephon Clark, an unarmed 22-year-old man who was shot and killed by police in Sacramento on March 18.

“We must help each other, we must do our own investigation,” she said. “I would not want this to happen to any mother, but it has happened to so many mothers.”

The group has scheduled another meeting with O’Malley on April 11 to continue the conversation.

Tindle’s family is also pursuing a lawsuit against BART police and Mateu with prominent civil rights attorney John Burris.

The District Attorney’s office declined to comment after the meeting with Tindle’s family Monday.

The shooting remains under investigation by the Oakland Police Department and the Alameda County District Attorney.

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