The witness who is also a gang member was shackled and chained up but still managed to sink into the corner of the courtroom and avoid the 25-year-old.
Authorities in Salt Lake city released footage on Monday from a federal courtroom that shows a USA marshal shooting dead a defendant as he attempted to attack a witness with a pen.
In a statement obtained by Deseret News US District Court Judge John Dowdell said the video contradicts the plaintiff's argument that Angilau stopped posing a danger within less than one second of launching himself at the witness stand.
The judge in the case declared a mistrial, and the USA marshal was later cleared of any wrongdoing.
Tenifa had been on the witness stand for 22 ½ minutes when the video shows Angilau standing up from his seat beside his defense attorney, picking up a pen from the defense table and charging. "Drop the pen out of your hand".
"Those last three shots were all after he's been shot once down on the ground in the back. There was no necessity to use force".
The unidentified United States marshal was cleared of any wrongdoing by the Federal Bureau of Investigation shortly after the shooting and a review board found the use of force was within agency policy. He said it is up to the them to decide if they want to appeal the judge's ruling dismissing their lawsuit.
Faces of the judge, attorneys and jurors are blurred out and the agency declined comment about the release of the video. Dowdell sided with Cleary's order Friday.
The family had argued that Angilau was armed only with a pen, and the four shots fired constituted an excessive use of force. Warning: Viewers may find the video disturbing.
The media took no position on whether the shooting was justified but claimed the video is a public record that documents a newsworthy event in a public courtroom.
Video of a deadly courtroom shooting has been released.
However, Judge Dowdell said that the marshal - referred to as Jane Doe - stopped the attack.