Earlier this month, the Ninth Circuit Court of Appeals heard the first Oral Argument of the case Doğan v. Barak. This hearing comes after decades of legal arguments over the degree to which foreign officials are immune to legal prosecution.

The case involves Turkish-American Furkan Doğan, who was killed by the Israel Defense Forces while on a flotilla mission organized by various humanitarian groups bringing aid to Gaza. He was 18 when he was allegedly shot five times, once at point-blank range, according to the United Nations Human Rights Council.

The UNHRC stated in a report that "Israeli forces carried out extra-legal, arbitrary and summary executions prohibited by international human rights law."

Doğan's lawyer, Brian Olney, agrees with this assessment. "That's exactly what it was," he said.

"I don't know what other word you would use to describe shooting someone in the head at point-blank range," he said.

Doğan's parents blame Ehud Barak, the defense minister of Israel at the time, for ordering what they say was an "extrajudicial killing." In October of 2015, Doğan's parents filed a civil lawsuit against Barak, citing violations of the Torture Victim Protection Act, Alien Torture Claims Act, and Anti-Terrorism Act.

Judge Otis Wright dismissed the case in October of 2016 on the grounds of the foreign official immunity doctrine, a customary international law that protects a wide range of actions taken by high-ranking officials. Doğan's parents appealed the decision.

As the two sides of this case continue to argue, legal questions remain unanswered.

One critical legal question is "how much deference courts should give to the executive branch," said William Dodge, a UC Davis law professor.

The other legal question is "whether Barak ordered the raid in his official capacity as defense minister," Dodge said.

If so, Doğan would be immune under international law, he said.

U.S. courts have previously faced questions of international immunity, and have ruled both to preserve immunity and to hold foreign officials accountable.

In Matar v. Dichter in 2009, the Second Circuit Court of Appeals dismissed the case against Avi Dichter, the former director of Israel's General Security Service, after he was charged with dropping a 1000-kilogram bomb on a densely-packed apartment building in Gaza. The court sided with the State Department's suggestion of immunity in its decision.

In 2010, the Fourth Circuit Court of Appeals refused to dismiss the case Yousuf v. Samantar against Mohammad Ali Samatar, former prime minister of Somalia. Samatar was charged with "torture, arbitrary detention and extrajudicial killing," according to court briefings. The court continued the case against the recommendation of the Obama Administration and ultimately ordered Samatar to pay $21 million to the plaintiffs.

While these cases resolved the issue of immunity for foreign officials through different outcomes, the settlement of Doğan v. Barak is still unclear.

The judges of the Ninth Circuit have not yet indicated when they would rule on this case.

The State Department declined to comment for this story.