After Dallas police officers used a bomb-carrying robot last month to kill the sniper Micah X. Johnson, it was widely reported that the incident marked the first time an American law enforcement agency had used that technique. But it appears that the bombing was not only unprecedented, but utterly unplanned-for: According to the Dallas Police Department’s open records team, the department has no written rules, guidelines, or protocols for how or when to use bomb-carrying robots against suspects.

During two separate discussions of Black Lives Matters protests on Tuesday, Donald Trump claimed that people have called for moments of silence for Micah Johnson, the gunman who killed five police officers in Dallas and injured nine others, without specifying who or where.

Today in Dallas, the city held a memorial service for the five officers killed by Micah Johnson last week. The service was attended by Barack and Michelle Obama, among others. It was, as you would expect, a somber affair for everyone—everyone except George W. Bush, who was ready to fucking party.

Dallas Police Chief David Brown detailed the moments leading up to the death of Micah Xavier Johnson—the 25-year-old Army veteran who fatally shot five Dallas police officers on Thursday night before police killed him with a robotic bomb—in an interview with CNN’s “State of the Union” on Sunday.

During a press conference Friday, Dallas Police Chief David O. Brown revealed that the fourth suspect in the Dallas attack died not by a self-inflicted gunshot wound, as had previously been reported, but by a bomb detonated by police officers. It appears to be the first time law enforcement has used such a tactic on U.S. soil.