During the final phases of the Last Great Time War, when the War Doctor had turned against the Time Lords, the Patriarch of the House of Stillhaven opposed Lord President Rassilon's plan to destroy time itself, (PROSE: Lords and Masters) along with the Woman. (TV: The End of Time)
Rassilon condemned them to stand behind him in the Panopticon and cover their faces "as monuments of their shame, like the Weeping Angels of old", (TV: The End of Time) and had their names erased from time as further punishment. (PROSE: A Brief History of Time Lords)
Behind the scenes
The character is never given any identification on screen. In the version of the script published on the BBC Writers Room website, the character is simply identified as Male Weeping Time Lord. He is played by an unknown actor.