Charlie Kirk's suspected assassin Tyler Robinson donned an anti-suicide vest as he made his first court appearance charged with the capital murder of the conservative star.

Robinson, 22, stared stonily at the web camera with unkempt facial hair as he appeared via video link before a court in Provo, Utah, on Tuesday afternoon.

He spoke only to confirm his identity, and gave a solemn nod as the short hearing closed.

Robinson faces seven counts - including a capital murder charge - over the shooting of Kirk, 31, at a Utah Valley University event in Orem on September 10.

Prosecutors said Tuesday that they plan to seek the death penalty for the alleged murderer if convicted.