The United Nations is considering the potential for a ban on certain types of autonomous weapons.
In a speech at the Fordham University School of Law Mr Johnson said: ‘The idea is motivated by a desire to rein in the president’s constitutional authority to engage in armed conflict and protect the nation, which is the very reason it has constitutional problems.’
The Huffington Post reports that the idea of a court to police drone killings was raised by Maine Senator Angus King. The idea gained weight after being praised by the editorial board of The New York Times, which compared it to the Foreign Intelligence Surveillance Court.
Supporters of the idea suggest that the court would legitimise and bring credibility to the secretive process the administration uses to decide who to kill in the name of the war against al Qaeda.
Mr Johnson admitted that the supporters had a valid point, but argued that the Constitution names the president as commander-in-chief, and he or she ‘cannot assign part of it away to another branch of government, nor have it taken away by an act of Congress’.
Mr Johnson left his position at the pentagon three months ago after spending four years in the department’s top legal role.