Family members of U.S. Navy Lt. Ridge Alkonis demonstrated outside Camp Smith, Hawaii, as White House national security adviser Jake Sullivan met there with Japanese and South Korean officials to protest what they said was their relative's unfair three-year prison sentence he is serving in Tokyo, American Military News reported on Sunday.

Alkonis, a 34-year-old father of three, is in jail in connection with a car crash in Fujinomiya, Japan, that killed two people.

Last year, Alkonis was driving to his home in Japan with his family after a hike on the 8,000-foot Mount Fuji when he suddenly lost consciousness midsentence while speaking to his daughter and crashed into several parked cars, killing two people.

Alkonis was unconscious for several minutes after the crash, and a neurologist later told him that he had suffered from altitude sickness, which can affect people at altitudes of 8,000 feet or greater.

But the judge in the case said Alkonis had not traveled high enough to have suffered from the sickness and sentenced him to three years in jail for negligent driving.

His supporters allege that his trial was not conducted fairly and that throughout the case the family of victims used connections in an attempt to have a harsh sentence imposed.

"The son-in-law of one of the victims is a prosecutor in the High Prosecutor's Office, which largely supervises prosecutions in that area," said Jonathan Franks, a spokesperson representing the Alkonis family, according to American Military News. "There are markers that they exercised inappropriate influence ... the daughter of one of the victims, who's an attorney who represented the family, was seated right behind the prosecutors' counsel table; it was a pretty clear message."

According to Japan's Ministry of Justice, of the 1,071 people convicted of negligent driving resulting in death during the previous year only 70 (6.5%) were sentenced to prison time, while the remaining 1,001 were given a suspended sentence, Stars and Stripes reported.

"Our thoughts and our prayers completely go out to the family in this tragedy," Seth Hannemann, a relative of Alkonis, told American Military News. However, "it's salt in the wound to further aggressively attack Ridge for an accident that haunts him and that happened under medical emergency circumstances."

At the same time as the demonstration at Camp Smith last week, Alkonis' wife Brittany and their three children were protesting near the White House in an attempt to enlist President Joe Biden's help in securing his release from prison.

• Do You Know the Signs of Acute Mountain Sickness?
• How Japan Went From Our Fanatical Enemy to Loyal Ally