Jakarta: Australian permanent resident Jessica Kumala Wongso had been so convinced she would be found innocent of murdering her friend with a cycnaide-laced coffee she had packed her clothes to go home.

But on Thursday evening the packed Jakarta Central District Court applauded as three judges sentenced her to 20 years' jail for the premeditated murder of Wayan Mirna Salihin, a crime they said was even more cruel because she had killed her own friend.

Wongso blinked rapidly as the judges delivered their stinging verdict but her face remained impassive.

"I don't accept this verdict because this is unfair and one-sided," said the 28-year-old, who had told her family not to attend the verdict.

Her lawyer, Otto Hasibuan, said they would appeal.

"Of course we are disappointed ... I told Jessica don't cry otherwise the judge ... will be happy," Mr Hasibuan said.

He had tried to prepare his client for the worst: "I told Jessica: 'You have to prepare a space in your mind for the bad thing that may happen'. She said: 'I don't want to think like that because I am not guilty.'

About 500 police were on standby in front of the Central Jakarta District Court as three judges delivered the long-awaited verdict in a sensational trial broadcast live on national television in Indonesia..

Ms Salihin, 27, died on January 6 after drinking a Vietnamese iced coffee that Wongso had bought for her at the glitzy restaurant Olivier in a central Jakarta shopping mall.

The prosecution said the emotionally unstable Wongso poisoned her friend to avenge her pain over Ms Salihin's criticism of Wongso's Australian ex-boyfriend.

The two friends had studied together at Billy Blue College of Design in Sydney.

The judges said aggravating factors were that she had never admitted her crime and had killed her own friend.

However on her side were her youth, the fact she had never committed a crime before and could change.

The crowd cheered as Ms Salihin's father, Edi Dermawan Salihin, said: "I can't say anything other than Allahu Akbar (God is the Greatest)".

"Allah is everything, Allah can show who is cruel, who is evil, all has been proven today," Mr Salihin said. "She sadistically poisoned Mirna."

Mr Salihin said Wongso may have been given the death penalty if Indonesia had not given a guarantee to the Australian Federal Police that it would not be imposed.

"A promise was made. Indonesia is a nation that keeps its promises to Australia. What can we do? The important thing is that it has been proven that Jessica was the perpetrator, that is all."

The trial, which provided a ratings boost for the TV networks, had all the plot points of a soap opera: beauty, youth, revenge, jealousy, murder, intrigue, inconclusive evidence and a murky motive.

Talk shows dissected Wongso's inscrutable demeanour during the trial, which many interpreted as evidence of a cold heart, and Vietnamese iced coffees became the ghoulish drink du jour at cafes throughout Jakarta.

It was speculated that Wongso was jealous of her beautiful friend, who had recently married.

Wongso insisted to the end she was innocent. "I swear I am not a murderer," she told the court during the trial. "Mirna knows I never poisoned her."

She said there was "nothing left in me" after the trial, which had been filled with bitterness. A nadir was the re-enactment of Ms Salihin's death at Olivier restaurant, during which people screamed "murderer" at her.

"Only God knows what has happened," Wongso said.

Mr Hasibuan had argued there was no motive for the murder.

He said it didn't make sense that Wongso would travel all the way from Sydney to Jakarta to murder her friend merely because Ms Salihin had advised her to break up with her ex-boyfriend.

Mr Hasibuan also pointed to the testimonies of three Australian experts who said there was no proof cyanide was the cause of death.

Toxicology reports tested negative to cyanide in gastric fluid, bile, liver and urine 70 minutes after her death and only a small amount of cyanide was found in her stomach several days later.

"These [toxicology] results show there is no evidence of cyanide ingestion," Australian forensic toxicologist Michael Robertson told the court.

Defence expert witnesses were also critical that a full autopsy had never been conducted, saying death by natural disease could not be ruled out.

Australia took a keen interest in the trial. The Australian Federal Police provided assistance after receiving an undertaking the death penalty would not be imposed.

Death is the maximum punishment for premeditated murder in Indonesia.

NSW police provided an insight into Wongso's tumultuous life in Australia. Multiple police reports were read to the court, mostly relating to Wongso threatening self-harm.

It was also revealed that her Australian ex-boyfriend, Patrick O'Connor, had obtained an interim restraining order against Wongso, fearing she would become violent after their split.

Wongso's ex-boss at the NSW Ambulance service, Kristie Carter, painted a picture of a manipulative, scheming and emotionally unstable person who had "two different personalities".

Wongso had said "you must die and your mum must die" when Ms Carter had refused to help her.

She had also told Ms Carter at one point: "If I wanted to kill someone I surely know how, I can get a pistol and I know the right dose".

Ms Salihin's supporters, who wore white T-shirts saying "Justice for Mirna", were told by police to enter the court through the right door, while Wongso's supporters entered through the left.

Asked if the family was depressed over the case, Wongso's mother Imelda, who was not present in court, told INewsTV: "We are not depressed. We are destroyed."

with Karuni Rompies

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