Police said the robot can see in the dark and assess how safe it is for officers to enter an apartment or building where there may be a threat.

"The NYPD has been using robots since the 1970s to save lives in hostage situations & hazmat incidents. This model of robot is being tested to evaluate its capabilities against other models in use by our emergency service unit and bomb squad."

The robot has its sceptics. Democrat politican Alexandria Ocasio-Cortez described Digidog on Twitter as a "robotic surveillance ground" drone.

Jay Stanley, a senior policy analyst with the American Civil Liberties Union, said empowering a robot to do police work could have implications for bias, mobile surveillance, hacking and privacy.

Some groups are worried that the dog could get a gun and be used to remotely kill black people criminals.

"We do see a lot of police departments adopting powerful new surveillance and other technology without telling, let alone asking, the communities they serve. So openness and transparency is key", Stanley said. 

However Keith Taylor, a former SWAT team sergeant at the police department who teaches at John Jay College of Criminal Justice said that a mobile device that can gather intelligence about a volatile situation remotely has "tremendous potential" to limit injuries and fatalities.,

The Times reports that Boston Dynamics has been selling the dog since June. It's also already being used by the Massachusetts State Police and the Honolulu Police Department the robot, has a starting price of about $74,000.