Myisha Carrion said she, her child's father, Lucious Davis, and his sister were backing out of a driveway when police officers pulled up.
"We asked them what is the reason and they're not saying anything. They're telling us to shut up," Carrion said.
Davis was arrested and, while his hands were cuffed behind his back, one of the officers punched him in the face as he tried to get off the hot hood of a car, Carrion said.
Community activist Quanell X said the officers then went into the home.
"Then they come in the home, without a search warrant, and search the home, come back out with a shotgun. Then give the young man they beat up a shotgun charge," he said.
Davis was charged with being in possession of a firearm and criminal mischief.
According to court records, Davis has a long criminal history, but has never been charged with a violent crime.
His rap sheet shows charges of driving with a suspended license and possession of marijuana.
"It doesn't matter about his background