Sandra Gregory, a British teacher, was last night beginning a 25-year sentence in a Thai prison after being found guilty of heroin trafficking.
A Bangkok court freed her co-defendant Robert Lock, 30, from Cambridge, whom she claimed had promised her money and who has maintained his innocence since their arrest in 1993. He will remain in prison pending appeal by the Thai authorities.
Gregory, 30, from Sowerby Bridge, West Yorkshire, was initially sentenced to the maximum penalty of death, but her admission of guilt persuaded the court to reduce her sentence.
Friends in Bangkok say that she has consistently maintained that she was set-up by Mr Lock, who offered to pay her pounds 1,000 for carrying the 3.6oz of heroin through Bangkok airport. She is said to have had no previous association with hard drugs, although she may have been an occasional user of soft drugs. She cried throughout the court session yesterday and told reporters that her sentence was "unfair".
Gregory alleged that Mr Lock had promised to pay her because she needed money for a trip home, in order to get medical treatment. He denied this story, saying that he had only met Gregory by chance while going to the airport.
Under an agreement between the Government and the Thai authorities, Gregory can apply next year to serve her sentence in the UK, since she will then have been in custody for more than four years.
If both governments agree to the move, then she would be able to transfer to a women's prison in England and be eligible for parole under British prison regulations. That would mean she would qualify for parole after serving half of her sentence. This would therefore mean a minimum of another nine years.
Gregory's lawyer said that she might benefit from an amnesty likely to be granted during the 50th anniversary celebrations of King Bhumibol Audulyadej's reign. The two most infamous British drug smugglers, the Birmingham teenagers Patricia Cahill and Karyn Smith, who were convicted of heroin smuggling in 1990, received a royal pardon after serving only a fraction of their respective 18-and 25-year jail sentences.
A relieved and beaming Mr Lock shook hands with his lawyers and reporters after the hearing, but remains in jail because the public prosecutor is appealing against his acquittal.
A Thai customs official told the court that Gregory was only searched because she arrived at the airport accompanied by Mr Lock. A British customs official also gave evidence that Mr Lock was suspected of trying to smuggle heroin and that the British had therefore passed this information to their Thai counterparts.
However, the court ruled that there was no direct evidence implicating Mr Lock, other than the testimony of Gregory, which was insufficient to justify a conviction.
The trial process was speeded up, following requests from the British government.
There are some 1,500 foreigners currently serving lengthy prison terms in Thailand on drug charges, 14 of whom are British. Earlier this month, considerable publicity surrounded the arrest of a 20-year-old Briton, Lisa Marie Smith, the daughter of a senior business executive based in Hong Kong.
Like Gregory, she too claims that she was tricked into carrying drugs.
Five inmates sentenced in Thailand have been returned to English jails to serve their sentences. And since 1985, 68 prisoners worldwide have been returned - 14 of those are still serving their time.
British officials rejected any suggestion that Mr Major could take up the case of Miss Gregory - as he did with Miss Cahill and Miss Smith - when he arrives in Thailand today for an international summit.
Mr Lock's mother, Lynda, who was not able to be in Bangkok for the trial, but heard the verdict on radio, said her son's acquittal was "wonderful news".
Mrs Lock, who has always maintained her son's innocence, said: "It was the only verdict. There was no evidence against Robert. Even the British Customs said they had no evidence against him."
The verdict on Gregory was fair because of the trouble she had caused her son by accusing him paying her to carry heroin, she claimed. "She smuggled drugs. She did it on her own," said Mrs Lock.
Gregory's 25-year sentence shocked the tiny community around her parents' home near the village of Pitcaple, Aberdeenshire.
Her father, Stan, said: "On a day like today you can imagine how we feel. What can you do for Sandra - what can anyone do for Sandra?" Mr Gregory said he would not comment further on the matter.