A "depraved" paedophile has been given one of the longest jail sentences ever imposed in Western Australia for abusing 22 children, including his own four, over a six-year period.
WARNING: This story contains details some readers may find distressing.
The 47-year-old man, who cannot be named to protect the identity of his victims, outwardly appeared to be a successful businessman with an expansive rural property, where families loved to socialise and let their children have play dates and sleepovers.
In reality, the man was a prolific child abuser who had set up secret recording devices in bathrooms and bedrooms to capture the children, all aged between two and 12, getting changed.
He also liked to strap a GoPro camera to his head and go into his children's bedrooms with a torch and record himself abusing them and their friends who were there for sleepovers.
Man drugged daughter so he could abuse her
The worst abuse was suffered by the man's youngest daughter when she was aged between two and eight.
District Court Judge Michael Gething said it was difficult to put into words the depravity of the offending against her, saying she had been so "comprehensively groomed" she regarded what her father was doing "as normal".
"This is one of the worst cases of its kind to come before the courts in Western Australia," he said.
On some occasions, the man gave the girl an over-the-counter sedative from what she called "a hidey-hole pocket" in his car, so she was asleep when the abuse happened.
In some of the recordings, the girl could be seen wearing clothing that had "Best Dad" emblazoned on it.
Judge Gething noted the offences happened everywhere — in the swimming pool, in the girl's bedroom, in the man's bedroom, at their holiday home — saying "there was no place for her that was safe".
The man also used social occasions at his home to abuse the children of his friends, including an Australia Day barbecue when he secretly recorded six of them, some while they were sleeping.
Wife found USB with recordings of children
The man's crimes only came to light when his wife, from whom he had then separated, came across a USB containing his recordings.
That led to a police investigation, described as one of the most significant child abuse investigations in WA, in which five detectives were forced to review 288 hours of recordings.
Millions of child abuse images and recordings were also uncovered on the man's electronic devices.
The man pleaded guilty to more than 420 charges and on Wednesday, as the victim's family and friends watched on in the public gallery, he was sentenced to 25 years jail.
Judge Gething referred to victim impact statements written by the parents of the victims, in particular the man's ex-wife, who described the abuse, particularly of her youngest daughter, as "incomprehensible".
"Never, would I think, she would be abused by the most important and trusted person in her life," she wrote.
Other statements from parents referred to the betrayal they felt that the trust they had placed in the man had been so grossly breached.
Offences committed in 'fog of drugs and alcohol'
Judge Gething gave the man a 25 per cent reduction on his sentence for his early plea of guilty, saying it had spared the victims and their parents from having to go through a lengthy court process, and a jury from having to view the material the man had recorded.
However, he said he did not accept the man was genuinely remorseful, despite saying in a letter to Judge Gething that his offences were committed in "a fog of drugs and alcohol" and he only now realised how selfish he was.
"I don't accept this," Judge Gething told the man.
"You knew, you just didn't care."
The man's sentence was backdated to the time of his arrest in July 2021.
He will have to serve 23 years before he is eligible for parole, meaning he will be behind bars until at least July 2044.
As he was being led away, one of the parents yelled out to him "I hope you have a lot of pain" while another said "rot in hell".