The brother of the woman charged with using an SUV to ram a Chicago Police officer’s daughter into a tree and run her over multiple times said she only lashed out because she was attacked by the victim first.

“She was fighting for her life,” Chynna Stapleton’s brother said after Stapleton, 24, was ordered held without bail Monday on a charge of first-degree murder in the death of Tatyanna Lewis.

Cook County prosecutors said Stapleton rammed Lewis with her Jeep Liberty, crushing her teenage rival against a tree, then driving the truck over Lewis several times.

“They jumped my sister. She was just trying to leave. Everybody is against her,” said Stapleton’s brother, dabbing the corners of his eyes with his T-shirt. “That lawyer, state’s attorney, whatever, doesn’t know what he’s talking about.”

Assistant State’s Attorney Jamie Santini said Stapleton and Lewis had an “ongoing dispute” over Lewis’ boyfriend, who also was the father of one of Stapleton’s three children. The romantic rivalry reached a deadly climax at 11:40 p.m. Friday, when the two women argued near the intersection of 114th Place and May Street.

The verbal dispute escalated to physical blows, Santini said, noting that “several people” also became involved and threw punches. Santini said Lewis was 19, though the CPD has said she was a year younger. Lewis was the daughter of a Chicago Police officer, police confirmed Sunday night.

After the fight ended, Stapleton climbed into her Jeep Liberty. Lewis kicked the side of the Jeep before walking off down May Street with her friends, Santini said.

Witnesses said they heard Stapleton shout “I’ve got something for you!” as she wheeled her Jeep around a one-way sign, jumped the curb and began driving over the sidewalk and yards along May street after Lewis and her group. A 13-year-old, who was not one of Stapleton’s children, was in the back seat of the Jeep as it went “barreling” over lawns and the sidewalk at Lewis, Santini said.

Lewis ran away, but tripped and the Jeep collided with her, plowing her into a tree, Santini said. Lewis’ body remained trapped against the Jeep as Stapleton put the Jeep in reverse and backed away from the tree, then put the SUV back into drive, rolling over Lewis with the front and rear wheels at least twice, before driving off down the parkway, leaving a trail of shattered car parts and vehicle fluids, Santini said.

Lewis, of the Burnside neighborhood, was pronounced dead at the scene, authorities said. An autopsy Sunday found she died of multiple blunt force injuries from being struck by the vehicle, and her death was ruled a homicide.

Police spotted Stapleton driving the damaged Jeep about 2 miles away, in the 100 block of West 115th Street moments later, and could see tree bark on the crushed front end and a crack in the windshield where Lewis’ head had struck the vehicle, Santini said. A police report said officers saw the Jeep had “extensive front-end damage, no headlights and heavy smoke coming from the engine.”

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Arguing for a $250,000 bond for Stapleton, Assistant Public Defender Chris Anderson said Stapleton had no prior criminal record, and anticipated prosecutors might reduce the charge to second-degree murder, because the brawl that preceded Lewis’ death had been incited by the dead teen.

“Is that the state’s intention?” Judge Maria Kuriakos-Ciesil asked Santini.

“The charge is first-degree murder,” he said.

“I don’t know what happened with this fight,” Kuriakos-Ciesil said. “It’s really sad to me that it’s always women fighting over men.”

Stapleton appeared in court Monday in black jeans and a hooded sweatshirt, her black hair in ringlets and without the bandage that had covered her chin in her booking mugshot. Family members pressed against the tinted glass window panes that separate the gallery from the courtroom, and several pounded against the glass as she was led out of the courtroom.

Community activist Andrew Holmes encouraged anyone who witnessed the attack, or who took video of the incident, to contact authorities.

“It’s unfortunate that there might have been people there that didn’t try to defuse the situation,” he said.

In a statement Monday, Fraternal Order of Police President Kevin Graham said, “Our hearts go out to the Officer and his family over this tragic and senseless killing. Such violence that results in the loss of life is all too frequent in the city. This case brings it home.”

Contributing: Tom Schuba and Matthew Hendrickson