The shocking footage shows the moment Siale Angilau, a member of the Tongan Crips gang, stood up, grabbed a pen or pencil, and ran towards the witness stand before launching his body over it in 2014.
Authorities on Monday released video of a US Marshal shooting an accused gang member who attacked a witness with a pen inside the Salt Lake City Federal Courthouse. He was not hurt, the "Daily Mail" reports.
The witness jumps out of the way and after various commands, including, "drop the pen" and "get on the ground", "Deputy Jane Doe", a U.S. Marshal, fired four shots, killing Angilau.
Donahue also pointed to a ruling Friday from US District Judge John Dowdell when he dismissed the Angilau's family's wrongful death suit, citing the video as proof that the US marshal who is referred to as Jane Doe in his ruling acted reasonably.
"The video completely contradicts the plaintiffs' argument that Angilau stopped posing a danger within less than one second of launching himself over the witness stand while making a stabbing motion with a pen in his hand", Dowdell wrote in a statement obtained by Deseret News.
The unidentified USA 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.
Angilau's lawyer, Robert Sykes, urged the judge to release the video so that the jury could see and decide if excessive force was used in the shooting.
He said the video shows that the marshal "panicked" and should have used other methods to subdue Angilau.
The video is muzzed to keep the judge, officers and any witnesses in the courtroom from being identified.
He points out that Angilau was already down on the ground for the final three shots and that a courtroom full of officers could have stopped him before he harmed anyone with the pen.
Skyes said: "There was no need to use deadly force".
A judge dismissed an excessive force case against an officer after he shot and killed a defendant, who hurled himself at a witness who was testifying.
Sykes said he's glad the video was made public, but the Angilau family wants justice.
They have not yet decided if they will appeal the judge's dismissal of their lawsuit. Dowdell sided with Cleary's order Friday.
He was the last defendant in the case to stand trial, with previous defendants being sentenced to 10 to 30 years in prison.
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.