BOSTON (REUTERS) - A federal judge in Boston on Thursday (Jan 28) rejected a last-ditch effort by two men to avoid being extradited to Japan to face charges they helped former Nissan Motor Chairman Carlos Ghosn flee the country.

The ruling by US District Judge Indira Talwani cleared the way for US Army Special Forces veteran Michael Taylor and his son, Peter Taylor, to be handed over to Japan, after the US State Department approved their extradition.

Judge Talwani said that "although the prison conditions in Japan may be deplorable" it was not enough to bar extradition.

She added the US has "sufficiently established that the actions the Taylors are alleged to have committed amount to an extraditable offence." Nissan and the Japanese embassy in Washington did not immediately comment.

The Taylors were arrested in May at Japan's request. Talwani put their extradition on hold on Oct 29 so she could hear their challenge to the State Department's decision.

Prosecutors say the Taylors helped Ghosn flee Japan on Dec 29, 2019, hidden in a box and on a private jet before reaching his childhood home, Lebanon, which has no extradition treaty with Japan.

Ghosn was awaiting trial on charges that he engaged in financial wrongdoing, including by understating his compensation in Nissan's financial statements. Ghosn has denied wrongdoing.

Prosecutors said the elder Taylor, a private security specialist, and his son received US$1.3 million (S$1.7 million) for their services.

The Taylors' lawyers argued they could not be prosecuted in Japan for helping someone "bail jump" and that, if extradited, they faced the prospect relentless interrogations and torture.

Ghosn in a court filing sought to support their claim, arguing he faced prolonged detention, mental torture and intimidation in Japan and the Taylors would face "similar or worse conditions."