U.S. Naval Officer Is Released From Jail in Japan After Yearslong Effort

Lt. Ridge Alkonis, the Navy officer who was imprisoned in Japan after killing two members of a Japanese family in a car crash, was on his way to the United States on Wednesday after a yearslong diplomatic effort to bring him home, Biden administration officials said.

Lieutenant Alkonis, 35, was released from prison after serving half of his sentence for negligent driving. Under the terms of the International Prisoner Transfer Program, set in place by a treaty between the United States and Japan, he was likely to continue serving his sentence in the United States, administration officials said.

The length of his incarceration will be set by the U.S. Parole Commission, an independent part of the Justice Department, officials said. The commission could reduce his sentence or allow him to serve part of it in home confinement. Lieutenant Alkonis will remain in detention in the United States until the commission makes its decision.

The case involving Lieutenant Alkonis, a sailor stationed at the Yokosuka naval base south of Tokyo, was set in motion one afternoon in May 2021, when the minivan he was driving near Mount Fuji careened into the parking lot of a noodle restaurant, killing two people.

The fallout since the accident has strained diplomatic ties between Japan and the United States, with his family and supporters insisting that Lieutenant Alkonis had suffered from altitude sickness and had been denied due process in a foreign court system that gave little weight to his guilty plea and repeated apologies.

In Japan, however, Lieutenant Alkonis is widely viewed as a criminal whose actions took two innocent lives. The court, which found that he had fallen asleep after driving while drowsy, followed the wishes of the victims’ family to impose a “severe penalty” in the case, sending the American to prison for three years.

Officials said President Biden was personally involved in discussions that led to the lieutenant’s release. But the officials described the conversation as highly sensitive because the president and his top aides did not want to insult the Japanese government by suggesting that they did not respect that country’s judicial system and need for accountability.

The family of Lieutenant Alkonis had mounted a long campaign to bring him home, and members of Congress have joined the fight, arguing that he suffered a medical emergency while driving and should not be held culpable for the deaths that resulted.

Senator Mike Lee, Republican of Utah, has led the effort to demand the sailor’s return. He has repeatedly threatened to push for a rethinking of the U.S.-Japan military cooperation agreement if they do not allow Lieutenant Alkonis to return home.

“If you transfer Lieutenant Alkonis back to the U.S. before midnight on Feb. 28, 2023, we will do our best to forget that this whole thing never happened,” Mr. Lee wrote in February. “It will be hard, but we will try.”