The family of a teenager shot and killed by a MARTA police officer last October is suing the regional mass transit agency.

The parents of Joetavious Stafford, 19, filed a complaint on Tuesday in Fulton County Superior Court claiming that the officer, Robert Waldo, was negligent when he responded to a fight at the Vine City MARTA station.

"Waldo's actions, in shooting Joetavius Stafford, were done oppressively, maliciously, corruptly or without authority of law," the lawsuit alleges. "... punitive damages are required in an amount sufficient to adequately punish and deter Defendant Waldo."

The suit names Waldo and MARTA as defendants, and claims that Stafford's death was unwarranted.

"As a direct and proximate result of the tortious acts and omissions of Defendant MARTA and Defendant Waldo, Joetavius Stafford experienced conscious pain and suffering, and ultimately a wrongful death," the lawsuit says.

Stafford was involved in a brawl outside the Vine City MARTA station after high school football games the night of Oct. 15, 2011, at the nearby Georgia Dome.

Someone fired a shot, and Waldo ran toward the melee, subsequently firing several shots, witnesses have said and MARTA has admitted.

But MARTA officials have maintained that Waldo believed Stafford was armed.

The lawsuit claims differently, however.

"Waldo did not reasonably believe that Joetavius Stafford posed an immediate threat of physical harm to ... Waldo or others," the complaint says.

Waldo, 31, resigned in March, according to records obtained by the Atlanta Journal-Constitution from the Georgia Peace Officer Standards and Training Commission, the state organization that certifies police.

MARTA officials reached Thursday by phone declined to comment, citing the pending litigation.

The GBI was initially called in to investigate the shooting, but turned the investigation over to the Fulton County District Attorney's office, which is still investigating.

An autopsy showed that Stafford was shot once in the chest and twice in the back.

District Attorney Paul Howard Jr. told the Atlanta Journal-Constitution in January that investigators discovered a gun -- separate from Waldo's -- but wouldn't say where the gun was found or whether there was any indication that Safford was in possession of the weapon.

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