A father has lashed out at his daughter's killer, punching him in the head and sparking a frenzy in a US court.Dwayne Smith was on his way to the front of the Detroit courtroom to give a victim impact statement when he crossed paths with Clifford Thomas, who was convicted of the involuntary homicide of three-year-old Jamila Smith along with the child's mother Jasmine Gordon, the Detroit Free Press reports.Footage of the attack shows Mr Smith lean in and land a hard blow on Thomas, who had his back to his attacker.Thomas immediately turns and squares up but Mr Smith has already been restrained by a security guard.Gordon cries hysterically and repeats the word "Jesus" as her lawyer John McWilliams tries to console her."It was pretty scary," the lawyer said."I'm glad nobody was seriously hurt".Gordon's daughter died of multiple blunt force trauma injuries in September last year with her death ruled a homicide.Earlier this month Thomas and Gordon were convicted of involuntary manslaughter and were awaiting sentencing when the courtroom attack occurred.Mr Smith was not allowed to return to the court and was lucky to escape charges."No charges were pursued against those involved as the judge declined to hold Dwayne Smith in contempt of court," Paula Bridges, a spokeswoman with the Wayne County Sheriff's Office saidGordon was sentenced to seven to 15 years for involuntary manslaughter and 14-25 years forfirst-degree child abuse as an aider and abettor, which will be served concurrently.Thomas was sentenced to six to 15 years for involuntary manslaughter and one to two years for resisting and obstructing a police officer.