Victim or Criminal? A U.S. Navy Officer’s Imprisonment in Japan.

Tomoko Ichihara’s family was wrapping up a birthday lunch near Mount Fuji when celebration turned to horror.

A silver Toyota drifted across a road and careened into the parking lot of a noodle restaurant, crushing Ms. Ichihara’s brother-in-law and mother between cars and leaving them with fatal injuries.

The minivan’s driver, a U.S. Navy lieutenant, would eventually be sentenced to three years in a Japanese prison. To his supporters, the officer, Ridge Alkonis, is a model sailor who was singled out for harsh treatment by a foreign legal system after a crash they say he could not have prevented.

His wife has called the sentence a miscarriage of justice and campaigned for his release, pleading her case to President Biden this month in a brief exchange after his State of the Union address.

In Japan, however, Lieutenant Alkonis is widely viewed as a criminal rightly imprisoned for taking two innocent lives.

A court found he had been negligent by falling into a “state of drowsiness” at the wheel, rejecting his assertion that he had lost consciousness while suffering from altitude sickness. His sentence, despite claims by his backers, was in line with penalties given to Japanese defendants in similar cases resulting in multiple deaths, experts say.

Lieutenant Alkonis, 34, struggled to navigate Japanese customs and legal bureaucracy after the crash. He pleaded guilty to negligent driving in hopes of receiving a suspended sentence. He wrote letters of apology and paid the bereaved families about $1.6 million, through insurance money and cash from himself and friends.

But sentencing decisions in Japan put significant weight on the wishes of victims’ relatives, and in this case they asked the judge to render a “severe penalty,” calling Lieutenant Alkonis’s actions after the crash insufficient and saying he had not fully acknowledged the seriousness of his crime.

While American lawmakers have said that Lieutenant Alkonis was denied due process, the Status of Forces Agreement governing the 55,000 U.S. troops in Japan does not shield them from the Japanese legal system or give them a right to a lawyer during questioning.

“I am not saying the Japanese justice system has no issues, but it’s just natural that suspects are not allowed to see lawyers,” said Takashi Shinobu, a political scientist at Nihon University in Japan.

Lieutenant Alkonis’s supporters in Congress argue that he should be allowed to serve out his sentence in the United States. Some TV commentators have accused the American military of giving him only lukewarm support in hopes of preserving strong relations with Japan, where tensions over the large U.S. military presence have flared at times after troops have been accused of crimes.

Senator Mike Lee, Republican of Utah, warned on Twitter this month that he would scrutinize security ties with Japan if the sailor was not on U.S. soil by Feb. 28.

The interventions have created a diplomatic distraction for two close allies that are increasingly working together to counter threats from China, Russia and North Korea.

News reports about Lieutenant Alkonis swirled around a trip to Washington in January by Prime Minister Fumio Kishida of Japan. When the officer’s wife, Brittany Alkonis, 35, attended the State of the Union address at the invitation of a Republican congressman, Mr. Biden told her afterward that the United States would not give up on the case.

“My kids are counting on you,” she replied.

Japan’s justice and foreign affairs ministries declined to comment. The U.S. Embassy in Tokyo said the State Department was working with the Pentagon to “provide all appropriate assistance.”

Lieutenant Alkonis’s accident happened shortly after 1 p.m. on May 29, 2021, as he was driving with his wife and their three children, now 5, 7 and 9. They were on their way to eat pizza and ice cream after visiting Mount Fuji.

The lieutenant, who was stationed at the Yokosuka naval base south of Tokyo, “fell asleep” at the wheel, the U.S. Navy said in an accident report obtained by The New York Times, and his Toyota left the road and slammed into five cars outside a restaurant. Seiko Sano, 85, and Takeshi Endo, 54, later died from their injuries. One of Ms. Sano’s daughters was injured and hospitalized for about a week.

In court, Lieutenant Alkonis said he “should have immediately stopped my car” after he felt his arms momentarily go weak about five minutes before he crashed.

He had also been quoted as saying during his interrogation that he felt “drowsy” before the accident — a word he later told his wife had been mistranslated in a statement he signed. At trial, he said he had been suffering from “acute mountain sickness” just before the accident, referring to a diagnosis he had received from a doctor.

The judge said it was hard to believe that Lieutenant Alkonis had suddenly fallen unconscious because of mountain sickness, in part because he had driven to a lower elevation before the accident.

Peter Bärtsch, a specialist in high-altitude illnesses at Heidelberg University in Germany, echoed the judge’s assessment in an interview, saying that a sudden loss of consciousness because of mountain sickness would not have been possible under the circumstances.

Beyond the medical questions, the sentence also hinged on perceptions of how Lieutenant Alkonis had interacted with the victims’ families in the hours, days and weeks after the accident.

He said at trial that he had done his best to help the victims at the scene. He also said that, in addition to the restitution payment — a custom in Japan — he had made efforts to apologize to the families, a statement supported by email correspondence that his wife provided to The Times.

But the apology letters were “not accepted,” Lieutenant Alkonis said.

Ms. Alkonis said in an interview that the Navy and her husband’s Japanese lawyer had told the family that the victims’ relatives had no interest in expressions of apology.

“We really wanted to meet these people and have this healing moment where we say, ‘We’re so sorry for everything you’ve been through and we want to do what we can,’” she said. “But we were told, ‘That’s not appropriate.’”

The victims’ families asked the judge to sentence Lieutenant Alkonis to four and a half years in prison.

Ms. Ichihara told the court she was skeptical that Lieutenant Alkonis “truly realizes the gravity of the sin he committed.” She said that he had not done enough to help the two fatally injured people after the accident, and that his lawyer had not made contact with the victims’ families quickly enough.

The families could not be reached for comment. Lieutenant Alkonis’s lawyer said he had not received his client’s permission to comment on the case.

Lieutenant Alkonis, a Mormon who had previously worked as a missionary in Japan, began his three-year term in July after losing an appeal to have his sentence reduced.

Mitigating circumstances, including compensation for bereaved families, typically help reduce sentences in Japanese courts, said Mamoru Shibata, a law professor at the Nagasaki Institute of Applied Science.

“But in this case,” Professor Shibata added, “what’s significant was the bereaved families’ strong wish to punish him.”

Ms. Alkonis said she felt that the Navy had been overstating its support for her family in its communications with members of Congress.

The Navy declined to respond to specific allegations, but a spokeswoman, Cmdr. Katharine Cerezo, said it had “provided and will continue to provide Lieutenant Alkonis and his family with all support consistent with U.S. law and regulations.”

“This was a tragic event,” she added, “and we recognize its impact on the families of everyone involved.”