Vic dad admits abusing his baby twins

A Victorian man who admitted filming himself sexually abusing his baby surrogate twin daughters intentionally brought them to Australia to use for sex, police say.

His daughters were four weeks old when his eight-month campaign of sexual abuse began, after he had already spent years abusing his nieces.

The father, who cannot be named, last week pleaded guilty to 37 charges including trafficking children, producing pornography and 20 counts of sexual penetration of his own child.

Police say the man brought his biological twin daughters into Australia with the intention of using them for sex.

Between May 2013 and April 2014, he and his wife paid $44,000 to an overseas surrogacy service which resulted in the birth of twins.

He began abusing them one month after they arrived in Australia, according to a prosecution summary released by the court on Tuesday.

The twins were conceived with a donor egg and the man's sperm after he had been abusing his nieces for years, starting when they were aged four and six.

His wife said he had discovered a "new-found enthusiasm" to have children, following a failed attempt at IVF.

The man's wife of 26 years was not aware of or complicit in the offending, the summary says.

Their sexual relationship had deteriorated due to his need to wear women's clothing during sex, and by the time they moved to regional Victoria in 2006 were occupying separate bedrooms.

Police began investigating the man for producing child pornography in November 2014.

When they raided his home the following month, the man told his wife: "I'm a pedophile and I'm going to kill myself," the summary says.

Police recovered more than 26,000 child exploitation pictures and videos that included images and footage of the man abusing his twin daughters on 40 occasions in 2014 and the two nieces he abused for four years.

He had created between 20 and 30 videos of himself abusing the infant girls, which he did on a weekly basis, and there were other incidents he didn't film, police say.

He shared the videos of his daughters online.

A combination of images and videos of his nieces numbered in the hundreds.

The man had conversations online under the username Candice or Candy, in which he says he regrets not having a child and says, "I was thinking money not pedo back then", according to the police summary.

Before the twins were born, the man expressed a preference for the babies to be girls and made name suggestions that included Candy.

The man is in custody and is expected to return to court in June.

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