The US Supreme Court stated on Monday that it would not review [order list, PDF] a lawsuit over a drone strike in Yemen that killed five people.

Earlier this year, the US Court of Appeals for the District of Columbia [official website] dismissed [decision, PDF] a lawsuit by the families of two Yemeni men allegedly killed by a US drone strike in 2012. The plaintiffs argued that two family members were victims of a “‘signature strike,’ an attack where the US targets an unidentified person … based on a pattern of suspicious behavior as identified through metadata.” Further, the plaintiffs argued that the drone operators waited until the two men joined the other three men to strike, in direct violation of international law, partly because the operators had ample opportunity to strike when the men were not nearby. A unanimous ruling by a three-judge panel upheld a lower court’s finding that the suit lacked the authority to question the government’s decision over the missile strike because “a court should not second-guess an Executive’s decision about the appropriate military response.”

The court went on to say that it is a congressional, rather judicial, power to check the executive branch’s authority of military power. It urged the Executive and Congress to work together to “establish a clear policy for drone strikes and precise avenues for accountability.”

Drone use [JURIST backgrounder] has been a controversial issue both in terms of small domestic drones and larger drones being used abroad by the US military. In October 2014 UN experts urged the international community to have greater accountability [JURIST report] and transparency when it comes to the use of drones. In August of 2014 the UN stated that if the US is to use drones they must comply [JURIST report] with international law.