Kidada Savage, 31, helped plot the arson. She was convicted in May of six counts of murder in aid of racketeering, retaliating against a witness and related offenses.
She faced a mandatory sentence of life in prison plus 10 years. After denying her request to delay sentencing, U.S. District Judge R. Barclay Surrick imposed the required sentence and said: "I have not heard any remorse from you."
"Quite frankly, the nature of this crime was barbaric," the judge said. "The crime was horrendous. . . . I don't know how you could live with yourself."
"Not guilty, your honor, that's how!" Conchetta Savage, Kidada's older sister, shouted from the gallery. After a U.S. Marshal approached her, the sister left the courtroom.
Earlier, Kidada Savage herself claimed to the judge that she had nothing to do with the killings. "Your honor, I was railroaded," she said. "The system is unjust.
"I would never hurt anybody regardless of that guilt verdict. I know I did nothing wrong," she said. "I will fight to the end because it's not true."
Assistant U.S. Attorney David Troyer told the judge that Kidada's role in the firebombing deaths "was essential." She reached out to Lamont Lewis, the hit man hired by her brother to carry out the firebombing. She showed Lewis the Coleman house.
The government alleged that Lewis got his cousin, Robert Merritt, involved, and both went to the house with gas cans to torch it.
A jury convicted Merritt of participating in the racketeering conspiracy but acquitted him of six counts of murder and the arson. Lewis pleaded guilty to the firebombing.
Kidada "chose to be a murderer of children," Troyer said. He also told the judge that Kaboni, 39, tried to help his sister delay her sentencing.
Housed in the "supermax" prison in Florence, Colo., facing the death penalty, Kaboni had spoken by phone on Thursday with Conchetta. "Get the names of attorneys, but don't pay anyone," Kaboni said, according to Troyer.
Troyer told the judge that Kidada was "manipulating the system" by trying to delay her sentence. The judge agreed.
Defense lawyer Teresa Whalen told the judge that Kidada grew up in a house that was the center of her brother's drug dealing. Her family had strong bonds of love and trust, and whatever Kaboni told Kidada to do, she did.
"The greatest punishment" for Kidada is being moved from the Federal Detention Center in Philadelphia, where she is close to her family, Whalen said. Lewis, who cooperated with the feds, and Merritt, still face sentencing.
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A jury convicted Merritt of participating in the racketeering conspiracy to commit murder but acquitted him of the arson. Lewis had pleaded guilty to the firebombing.