A criminal who held his daughter captive and raped her over decades has again requested an early release from jail.

Josef Fritzl, 90, was sentenced to life imprisonment over the incestual crimes.

His daughter was 18 years old when he locked her in the basement of his house in Austria in 1984 and, over the next 24 years, raped her thousands of times, fathering seven children with her. One of the babies died soon after birth.

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Now the regional court in the Austrian city of Krems confirmed Fritzl’s lawyer, Astrid Wagner, had submitted an early release request.

The lawyer had previously talked about the request on her podcast Plädoyer für Verbrecher (Plea for Criminals).

She claims the criminal now has dementia and therefore poses no danger to the public.

She also argued Fritzl had spent more than 15 years in prison and that the legal requirements for such a move had therefore been met.

“I think he deserves this chance too,” she said.

However, Wagner expects that it could still be some time before this happens.

Fritzl’s case came to light in 2008 and made headlines around the world.

His wife, who lived on the first floor of the house with the rest of the family, was unaware of his crimes, according to the authorities.

He told his family that his daughter had run away to join a cult and explained the sudden appearance of the three children by claiming she had returned and dropped them off.

Four of the children were held captive in the cellar with his daughter, while three lived upstairs with his wife.

In March 2009, Fritzl was sentenced to life imprisonment for murder by omission, rape, deprivation of liberty, aggravated coercion, slavery and incest. Fritzl took on a new surname in prison.

An earlier request for early release — seeking to be transferred to a nursing home — failed last year.

The court cited Fritzl’s high level of criminal energy and lack of preparation for a life in freedom.

If you or someone you know is impacted by sexual assault, domestic or family violence, call 1800RESPECT on 1800 737 732 or visit 1800RESPECT.org.au. In an emergency, call 000.

Advice and counselling for men concerned about their use of family violence: Men’s Referral Service, 1300 766 491.

If you need help in a crisis, call Lifeline on 13 11 14. For further information about depression contact beyondblue on 1300224636 or talk to your GP, local health professional or someone you trust.

—With CNN