By KYW community affairs reporter Cherri Gregg

PHILADELPHIA (CBS) — Less than a week after the City of Philadelphia released the names of the officers who shot Brandon Tate-Brown during a traffic stop last December, his family is asking the feds to step in.

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“They lied about what happened to Brandon Tate-Brown,” says attorney Brian Mildenberg, who is representing the family of the dead man in a civil suit against the city.

For months they’ve demanded the city publicly release evidence in the case.  Last week the city complied, releasing DNA reports and officer interviews whose details contradict some aspects of initial police reports of the shooting.

Now the family is demanding action, calling the earlier investigation a cover-up.

“These police officers, Commissioner Ramsey, need to be placed on desk duty immediately,” Mildenberg said in an open statement to the Philadelphia police commissioner.

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Mildenberg says the family wants the city’s district attorney to reopen the criminal investigation against the officers and are demanding that the US Department of Justice launch its own investigation.

“Accountability is all I’m asking,” says Tate-Brown’s mother, Tanya Brown Dickerson.

Mildenberg says the family is also seeking surveillance video and other details of police work at the crime scene.

Philadelphia DA Seth Williams issued a statement today saying he has no plans to reopen the investigation because what happened was, in his words, “tragic, not criminal.”  He says evidence showed that Tate-Brown reached for a gun several times before he was shot, adding that the man’s actions put the officers and bystanders in danger.

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