It is often written that not since Lindy Chamberlain has the Australian public been so gripped and divided by a criminal case.

In 2005, Ms Chamberlain-Creighton even penned a letter to Schapelle Corby. "My heart bleeds for you," she wrote.

But there is a glaring difference between the two cases. Ms Chamberlain-Creighton was eventually pardoned of the crime, her conviction was quashed and a coroner ruled a dingo had indeed taken her baby.

Corby has never proven her professed innocence.

Corby will return to Australia on Saturday a convicted drug trafficker who has served her jail time.

Philip Ruddock was the attorney-general at the time of Corby's arrest in 2004. He said in every case the Australian Government did what it could to assist those abroad.

"My principle recollection is that she (Corby) was of the view that the drugs were planted on her and endeavoured to try and prove that in the proceedings and it failed," Mr Ruddock said during an interview with the ABC.

One of Corby's key defences put forward by her legal team and supporters was that corrupt baggage handlers had placed the 4.1 kilograms of marijuana in her boogie board bag.

No evidence to support Corby's claims of innocence

But Mr Ruddock said there was never any evidence gathered by Corby's defence team or agencies in Australia, including the Australian Federal Police (AFP), to support that claim.

"You know, these were claims. It's never been proven that drugs were planted on her," he said.

"I'm sure every endeavour was taken to establish what is the truth.

"Now some parties might not like the truth, but I am sure that has always been the approach that the Australian Federal Police has taken and I have no reason to believe that they weren't investigating these matters and willing to share with those abroad the outcome of their findings."

In a statement to the ABC this week, the AFP confirmed interviews had been conducted during March and April 2005 with baggage handlers who could have had access to Corby's luggage.

"No information or evidence was uncovered that suggested drugs were planted in Ms Corby's luggage as alleged," the statement reads.

"The AFP conducted a range of enquiries and all reasonable steps were taken during the investigation of Ms Corby's allegations."

Widespread displeasure in Indonesia that Corby's sentence was slashed

Tim Lindsey, the director of Melbourne University's centre for Indonesian Law, Islam and Society, said it was always likely Corby would be convicted by the court in Bali because she could not produce evidence she was not guilty.

"Whatever the theories, whatever the controversy, whatever the arguments the evidence presented did not as a matter of admissible evidence support her innocence and so she was convicted," Professor Lindsey said.

Professor Lindsey said there were various theories put forward by Corby's supporters, her family, her lawyers and the media.

"They called in a prisoner to give evidence of a conversation he had heard which they said would support the baggage handler corruption theory but that evidence was of two other people's conversations," Professor Lindsey recalls.

"In Australia that would be hearsay evidence and wouldn't be allowed, and the same rule applies in Indonesia."

There were many theories put forward by Corby's family and supporters after her arrest. ( Bagus Othman: Reuters )

In the end it was the then Indonesian president, Susilo Bambang Yudhoyono (SBY), who guaranteed Corby a swifter return to Australian soil.

In 2012, he granted the Australian woman clemency, cutting five years from her sentence, a decision that was widely condemned in Indonesia.

Corby had been dubbed in the Indonesian press the "Ratu Ganja" or "Marijuana Queen" and there was widespread displeasure with SBY's decision.

Hikmahanto Juwana, an International Law professor at the University of Indonesia, was one of those who spoke out against the president's decision at the time.

"Of course there are various reasons why he granted clemency probably one of them is the aid pressure from the Australian Government," Professor Juwana said.

The Australian and Indonesian governments denied any deals had taken place to secure the clemency.

"At the time it was seen in the press in Indonesia and by the public as a concession by Yudhoyono to Australia," Professor Lindsey recalls.

Demonstrators in Jakarta expressed their anger at what they believed was a lenient sentence for Corby. ( Reuters: Darren Whiteside )

"He was seen as both conceding to a foreign country and being weak on drugs and took a lot of political flak for that decision."

Mr Ruddock said he was not aware of any political deals done.

"I wouldn't say to you that Schapelle's case has been very different to that of the Bali Nine or that of the young lass in Colombia," Mr Ruddock said speaking of the current case of Australian Cassie Sainsbury.

"They from time to time arise and the media gives them note and sometimes the party themselves use the media to try and assist in a way that they think might help their case.

"My judgement is that if people come to that view it is probably flawed because I can't see from any case I'm aware of the fact they have been dealt with through the media have produced different outcomes."

Corby prevented from profiting from conviction

The Proceeds of Crime Act should ensure Corby does not profit from the drug trafficking conviction. Mr Ruddock believes if the law is not watertight it should be fixed.

"I don't know if there are any claims that the law is flawed. If it were or if it were proven to be flawed I would expect the appropriate steps to be taken to cure the defect," he said.

In 2009, the Commonwealth Director of Public Prosecutions seized more than $120,000 made to Schapelle Corby's family from the sale of her book, My Story.

But according to the parliamentary library paper, Selling your story-literary proceeds under the Commonwealth Proceeds of Crime Act 2002, a much greater amount was transferred into an Indonesian account.

"Investigations by the Australian Federal Police revealed that, under the contract relating to My Story, payments totalling $267,750 had been made by Pan Macmillan publishers to an Indonesian account held in the name of Corby's brother-in-law," it said.

Mercedes Corby was married to Balinese man Wayan Widyartha at the time.

That money was not recovered.

"I don't think people should be able to say I'm going to go and rob a bank and I should be able to make money later you know by telling everybody about how I went about robbing the bank," Mr Ruddock said.

He said the focus should now be on securing a prisoner exchange deal with Indonesia.