Accused Australian paedophile Robert Andrew Fiddes Ellis – referring to himself in the third person – writes: "Mr Ellis is not the kind of man who deserves imprisonment.

"He paid the girls in full immediately after the liberties were taken and the law in full by his 16-week ordeal in the Polda (police) remand cell," the 70-year-old from Victoria says in the handwritten letter to his lawyer.

The "girls" to whom Ellis refers are children he allegedly sexually molested in Bali before paying them off with gifts of clothing, bikes, trips to the mall and cash.

Ellis is due to be sentenced in the Denpasar District Court on October 18 over the alleged sexual abuse of at least 11 girls aged between eight and 17.

The court heard the children were abused while he bathed them at his rented property in Tabanan.

Ellis' lawyer, Benny Hariyono, said last month his client's admission that he only committed these acts in Indonesia – specifically Bali – because he targeted girls with lesser education "got quite a reaction from the panel of judges".

Former Victorian police officer Glen Hulley​, whose anti-child sex exploitation organisation Project Karma helped facilitate Ellis' arrest, said: "This is by far the worst case I've ever seen of an Australian committing this kind of offence in Bali."

In 2014, Fairfax Media reported that Indonesia had eclipsed Thailand, the Philippines and Malaysia to become the number one destination for Australian sex tourists over the previous three years. Most started in Bali.

"Paedophilia is a big problem in Bali," Mr Hulley said. "What a lot of people don't understand is you won't see a lot of this stuff going on in tourist areas ... it's bad for business."

He said remoter areas, such as Karangasem and Amed in Bali's east, had been identified as child sex exploitation hot spots. "These are also a gateway to Lombok, the Gili Islands and Sumba – we have a lot of evidence of children trafficked from Sumba to Bali for child exploitation. Many end up in orphanages in Bali or on the street."

In 2014, there were about 255 instances of an Australian registered sex offender travelling to Indonesia – the equivalent of 21 a month.

However the Australian Federal Police said this has dropped significantly since a deal between the two countries in November 2014.

Indonesia agreed to refuse to allow Australian registered child sex offenders to enter the country when notified by Australian authorities.

Since 10 November, 2014 an estimated 166 Australian-registered child sex offenders were refused entry to Indonesia.

"Co-operative arrangements between the AFP and Indonesian authorities have contributed to an overall reduction of registered sex offender travel to Indonesia," an AFP spokesperson said.

"The average number of registered child sex offenders travelling to Indonesia per month has been reduced from 21 in the year 2014, to 10 in the year 2015, and currently five in the year 2016 to date."

Mr Hulley said there are three types of paedophiles in Indonesia: expats, such as Ellis, sex tourists and locals.

"Research shows that in south-east Asia, 85 per cent of child sex crimes are committed by local people but most NGOs only focus on foreigners who have committed these crimes."

Last week a 10-year-old girl was allegedly sexually molested after being lured into a car outside her home in Bali's capital, Denpasar.

Project Karma, an Australian-registered charity reliant on donations, is about to start training 20 Balinese civil police, known as Pecalang and Jaga Baya, as a joint taskforce of investigators to combat child sexual abuse in the Karangasem regency.

"Once those 20 are trained there is a program to train around 400 of these civil police," Mr Hulley said.

In May of this year Indonesian President Joko Widodo​ announced a regulation – effective immediately – that would allow judges to sentence child rapists to death or order that they be chemically castrated.

However Ellis will not be affected because the new regulation cannot be applied retrospectively. Instead prosecutors have requested 16 years' jail, which Ellis' lawyer argued is too severe.

Mr Hariyono said his client's actions were not intentional but done out of a "grandfatherly affection towards the children".

He said parents of the victims knew what was going on and had also received payments and gifts from Ellis.

Luh Putu Anggreni, from Lentera Anak Bali, an NGO specialising in children, said last month that it really upset her that Ellis felt his actions were justified because he paid the girls. "That he has every right to molest the girls because he already paid them."

In a letter that Ellis planned to read to the court – although his lawyers ended up reading an alternative defence – he says he can't believe that anyone who knows him is calling for him to be punished.

"Drawing the line at 16 years has been the way in UK, USA countries for a long time, and it seems has spread to Indonesia through its membership in the United Nations ... but it is not God's Law," he writes.

"I am solitary and unmarried and my sex instinct was not ministered to in my own country. In all probability my young friends desperately want me returned to them."

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