The Hawaii Supreme Court was scheduled to hear oral arguments Thursday morning on whether U.S. State Department special agent Christopher Deedy should stand trial a third time for a fatal 2011 shooting.

Deedy first stood trial for murder in 2013 in the shooting death of a Kailua man, Kollin Elderts, 23, in a Waikiki McDonald’s, but the jury was unable to reach a verdict and the judge declared a mistrial. Jurors were not given the option to consider finding Deedy guilty of manslaughter or other lesser charges.

Following the mistrial, the Hawaii Supreme Court, in ruling against the trial judge in two other cases, said juries must be given the opportunity to consider lesser charges in their deliberations. The justices also said even if a jury finds a defendant guilty of the higher charge, the verdict can be overturned if the jury was not given the option to consider lesser charges.

Deedy went on trial for murder again in 2014, with jurors given the option to consider finding Deedy guilty of manslaughter of Elderts, or finding that Deedy was under extreme mental or emotional distress when he shot Elderts.

The second jury was also unable to reach a verdict, and the foreman said jurors were hung on the manslaughter charge. At the request of Deedy’s lawyer, the judge then acquitted Deedy of murder. The judge refused Deedy’s request to dismiss the case and ordered him to stand trial again, this time for manslaughter. Deedy is appealing the judge’s order.

His lawyers argue that a third trial would violate Deedy’s constitutional rights against double jeopardy and legal prohibitions against allowing the government to continually take a defendant to trial until it gets a conviction. They also argue that Deedy cannot be tried for manslaughter because the prosecutor abandoned the charge in both trials by arguing against letting the jury consider it.

Deedy was 27 years old when he arrived in Honolulu in November 2011 to provide security for the multinational Asia-Pacific Economic Cooperation conference. He was and is still assigned to Washington, D.C. He was on Oahu barely 12 hours and had been out drinking with friends when he encountered Elderts in the McDonald’s restaurant on Kuhio Avenue.

The prosecutor says Deedy was drunk, started a confrontation with Elderts and did not identify himself as a law enforcement officer before shooting.

Deedy testified he was not drunk and that he shot Elderts to protect himself and others from being assaulted by Elderts and Elderts’ friend, Shane Medeiros. He said he showed Elderts his badge and identified himself as a law enforcement officer.

Elderts died from a gunshot wound to his chest.