Japanese authorities are expected to release Julie Hamp, the American who until last week had served as Toyota Motor Co.’s global communications chief, from jail without indicting her on drug charges, it was reported Tuesday.

The 55-year-old Hamp, who had been the highest-ranking woman at Toyota before resigning, had been held in a Tokyo jail since June 18th when she was arrested for allegedly bringing the drug oxycodone into Japan illegally. Authorities subsequently raided three different Toyota offices, including its headquarters in Toyota City. While the maker’s President Akio Toyoda voiced his support for Hamp shortly after her arrest, the New York-born executive last week tendered her resignation.

"The prosecutors appeared to have taken into consideration the fact that the 55-year-old American's act was not malicious and that she has already resigned from the post at the Japanese automaker," the Kyodo news service wrote on its English-language website, citing "investigative sources."

Hamp’s arrest and threat of prosecution prompted speculation that the case may have been influenced by the fact that she was a foreigner and one of the highest-ranking women in the normally male-dominated Japanese business world.

A separate report in the English-language Japan Times noted that since Hamp’s arrest, “The police have judiciously leaked information to bolster their case,” suggesting Hamp did not actually need the narcotic pain killer, and triggering such xenophobic headlines in local media as, “Diversification a Problem for Japan.”

Hamp's case also has drawn the attention of the U.S. ambassador to Japan, Caroline Kennedy, who earlier this year worked for the release of an American teacher who was arrested after importing a drug for attention deficit disorder, the Detroit News reported.

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Hamp was being held virtually incommunicado in a cell with other prisoners, none of whom was allowed to refer to each other by name, according to reports from Japan. She was allowed only one 20-minute visit from an outsider per day, along with contact with her lawyer. She could have been questioned repeatedly by authorities without a lawyer present, they said.

Under Japanese law, Hamp could have been held for up to 23 days without charges and could have remained in jail until a trial began. Japan aggressively prosecutes drug cases and authorities claim a conviction rate of around 99 percent.

Specific details of what actually happened have not been clear, but Hamp reportedly acknowledged using oxycodone for knee problems. The drug was apparently found in a shipment from the U.S. that contained jewelry. There are various reports indicating she either made the shipment herself or that the package was sent by a member of her family.

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A one-time senior PR executive at General Motors, Hamp resigned to take the top communications post at PepsiCo. She returned to the auto industry in 2012 to run Toyota’s top U.S. public relations office. In April of this year she was recruited by Akio Toyoda, the grandson of Toyota’s founder, to move to Japan, becoming not just the first foreigner to head communications but the first female in such a senior position anywhere in Japan.

Following her arrest, Toyoda staged a widely followed news conference in which he referred to Hamp as his “friend,” and an “invaluable” asset to the company. He also tried to deflect some of the criticism that followed her arrest, taking personal blame for not helping her properly prepare for the move to Japan.

“To me, executives and staff are like my children,” he said. “It’s the responsibility of a parent to protect their children.”

If anything, that news conference appeared to raise even more hackles in Japan. A media Q&A session was peppered with thinly veiled, derogatory questions about women and foreigners, according to reports that followed.

Authorities in Japan have not yet commented on the status of the case. A spokesperson for Toyota noted the company is now “trying to check” what will happen next.

Toyota appears to still be providing at least some assistance to Hamp, even though she resigned on July 1. The company said it accepted the resignation because of “the concerns and inconvenience that recent events have caused our stakeholders.”

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