Dallas attack suspect Micah Xavier Johnson ultimately died when officers sent in a robot, rigged to explode, in the area he was in. According to several law enforcement officials, this marks the first time such a robot was used lethally by an American police department.
Typically, those robots are used to defuse bombs, and for years, local police have been using models like the Northrop Grumman Remotec Andros to inspect suspicious packages
In January of 2015, Lodi police used a similar robot to disarm a pipe bomb found in a suspect's vehicle. It's a tactic, originally used in the wars in Afghanistan and Iraq, to deal with improvised explosive devices, better known as IEDs.
In those conflicts, there have been rare reports of the robots being rigged to explode to kill insurgents. But it's never been used in that way in the United States until now.
Dallas Police Chief David Brown said negotiations failed with Johnson.
"We saw no other options but to use our bomb robot and place a device on its extension for it to detonate where the suspect was. Other options would have exposed our officers to grave danger," Brown said.
Many legal and ethical questions remain about this decision, similar to the national debate over police using drones over american skies.
Elizabeth Joh, a law professor at UC Davis told the Associated Press that she questions the future use of such robots.
"If lethally equipped robots can be used in this situation, when else can they be used?", Joh asked. "Extreme emergencies shouldn't define the scope of more ordinary situations where police may want to use robots that are capable of harm."
One of the manufacturers of these machines, Endeavor Robotics, said they built them to save lives, not take them.
"Our whole purpose is to keep people at a safe distance from hazardous conditions, we've seen that in the wars in Iraq and Afghanistan with the IED threat," said Tim Trainer, Vice President of Endeavor Robtics.