The administrations policy of targeting American citizens for assassination is a direct and flagrant violation of our constitutionally protected rights. The DOJ white paper is laying out the authority to kill US citizens who are not actively participating in an armed conflict and without any proof that they are linked to a terror group other than the word of an "informed, high-level official of the US government". In that paper, it is stated that the Due Process clause and 4th Amendment protections that a citizen has "would not immunize him from a lethal operation."
Unless a US citizen is directly involved in a current, ongoing battle he should not be targeted by drone or other means. Evidence should be submitted and he should have the opportunity to stand before a court of law.