"How does the CIA's targeted killing program differ from the military's--and what are the implications of shifting one program into the other? Perhaps most important is that the CIA's program is 'covert'--which is to say it is not only highly classified, it's deniable under the law. That means the CIA, in theory, can lie about the existence of the program or about particular operations. The military's targeted killing program, however, is 'clandestine'--which means it is secret...
There's nothing in the law that says the military has to brief congressional committees about its lethal activities.