A representative from the American Civil Liberties Union told the U.N. Human Rights Council on Wednesday that the use of unmanned drones to kill suspected terrorists set a "very dangerous precedent."

Drones operated by the U.S. have been used to kill suspected terrorists in Afghanistan, Pakistan, Yemen and Somalia. While the drone campaign has killed top leaders of Al Qaeda, the legally dubious practice has received criticism from human rights advocates.

"The authority the United States claims today could be used tomorrow by nations with fair less respect for the right to life in particular and human rights in general," ACLU National Security Project Director Hina Shamsi warned.

Shamsi acknowledged that targeted drone strikes could be lawful in some circumstances, but said the U.S. had failed to establish any legal justification for the killings.

"It has cobbled together its own legal framework for targeted killing, with standards that are far less stringent than the law allows," she explained.

"Senior U.S. government officials have claimed self-defense and law of war authority to target and kill suspected terrorists in states with which and in which the United States is not at war, based on largely secret legal criteria, entirely secret evidence, and a secret process."

The Washington Post reported in April that the CIA and Joint Special Operations Command have been authorized to strike targets based solely on patterns of suspicious behavior that are detected through various means of intelligence — the actually identity of the target does not need to be known. Before April, the CIA and JSOC were only authorized to use drone strikes against known terrorist leaders whose location could be confirmed.

The New York Times later revealed the President was intimately involved in who was on the so-called kill or capture list, but the entire process is wrapped in secrecy. The Obama administration has also controversially defined “militants” as all military-age males in a given strike zone. Human rights groups have criticized the definition for underestimating civilian causalities.

Shamsi added that the U.S. should "disclose who has been killed, the number of collateral civilian deaths, and the outcome of any government investigation into mistakes or wrongful targeted killings," all of which the government has so far failed to do.

Watch video, courtesy of the United Nations, below:

[Drone via Paul Drabot / Shutterstock.com]