A WOMAN whose father locked her in a cellar for nearly a quarter of a century and had seven children by her will tell a court next week that she “tried to please him” in order to protect her daughter and sons from his abuse.

In filmed testimony, Elisabeth Fritzl, 43, will describe being assaulted by her father for the first time at the age of 11, when she defended herself against rape by “kicking and screaming”, according to sources close to the investigation.

Josef Fritzl, 74, who goes on trial next week for murder, incest, unlawful imprisonment and “enslavement”, is convinced he could serve fewer than 10 years in prison for what has been described as Austria’s most horrific post-war crime.

The trial will raise uncomfortable questions about Austrian society, highlighting police failings and a town’s astonishing blindness to what was unfolding beneath one of its main streets, where Fritzl held Elisabeth as a sex slave for 24 years in a warren of windowless, soundproofed rooms.

He will offer a shocking defence, claiming that his daughter was having sex when she was barely out of her teens. She smoked. She took drugs. She drank. He wanted to save her.

“He is not a monster,” Rudolf Mayer, Fritzl’s lawyer, said last week. “He loved his daughter in his own way.”

Fritzl locked her in the purpose-built cellar, forcing her to write a letter claiming she had run away to a cult. Their sexual relationship was “consensual”, he maintains - even though Elisabeth has described being chained to a wall while he raped her.

Elisabeth claims in her testimony that he also physically hurt her, without wanting to specify how.

Police found whips and handcuffs in the cellar, where she gave birth to one child after another without medical assistance in a case that has sickened the world.

One infant died shortly after birth and the corpse was incinerated by Fritzl, leading to a charge of “murder by omission”: he could have saved the baby if he had called a doctor, the prosecution argues.

Three of the children were taken upstairs and officially adopted by Fritzl and Rosemarie, his wife. Fritzl pretended that the babies had turned up on his doorstep and forced Elisabeth to write a letter claiming she had left them for him to look after.

In an attempt to gain sympathy, Fritzl will explain how he “cared for” his captives, taking them food, books and toys. He gave them a budgerigar, whose survival in the cellar meant that the air quality must have been adequate for humans, he will argue.

Elisabeth, for her part, talks about large rats that would, on occasion, appear. She managed to kill at least one of them, squashing it with a bucket.

Fritzl sometimes took her photographs of the “upstairs children”, which she put in an album. They have since been reunited as a family and live with Elisabeth under a new name.

Fritzl will tell the court that he had been planning to free them all along. He had begun work on converting part of the house upstairs for their use and asked Elisabeth to write a letter explaining that she had decided to come home.

His plans went awry, however, after Kirsten, their daughter, became seriously ill last year. Elisabeth persuaded Fritzl to let her go to hospital, where staff realised something was wrong and called the police.

In her video testimony, Elisabeth will tell the court how she began enduring Fritzl’s abuse as a child after he put pornographic magazines under her pillow.

She suffered psychological problems. She cut herself. She lost weight and was only 5 stone 10lb by the time she was locked in the cellar.

Fritzl has expressed no remorse beyond accepting that he is “not normal”. He has offered himself as a subject of study to Reinhard Haller, one of Austria’s top criminal psychiatrists, apparently in the hope that experts can help to prevent anything similar happening again.

Reviled as “das Inzest-Monster”, Fritzl may yet walk free surprisingly early. Legal experts believe it will be impossible to convict him of the murder charge. Of the remaining charges, rape is the most serious, carrying a sentence of up to 15 years. With good behaviour and parole he could be out in 10 or even five years.

“It is a spectacular crime but not in terms of the sanction envisaged under our antiquated criminal code,” said Raoul Wagner, a Viennese lawyer campaigning for changes in a system that “protects criminals” rather than victims.

“It is outrageous,” Wagner said. “There is no guarantee that Fritzl, if he lives to a ripe old age, won’t be a menace to women again.”

No questions were raised when Fritzl applied to adopt the children supposedly found on his doorstep, even though he had been convicted in 1967 of a rape for which he spent 18 months in prison. That is because, until recently, criminal records were erased in Austria 10 years after the completion of the sentence. “He could have been stopped if the information had been available to police,” Wagner said.

The case is just as embarrassing for social workers in the town of Amstetten, where the Fritzl family lived. They visited the house, but failed to notice signs of distress. Nor, apparently, did relatives or neighbours, although it has been suggested that some preferred not to see. Even Rosemarie, the wife, claims to have known nothing.

“We have an unfortunate tendency in this country of brushing things under the carpet,” said Hubsi Kramar, a theatre director who provoked outrage earlier this year by putting on a satirical play based on Fritzl. “We prefer not to look. Not to see.”

The regional capital of Sankt Pölten, where the trial will open next Monday, is preparing as best it can for a media invasion from around the world. Stands selling sausages are to be erected in the square. A guide to the area is being rushed out by the town hall.

In order not to prolong the national nightmare, however, a deal is rumoured to have been struck between the prosecution and the defence under which Fritzl’s lawyer will not appeal against the sentence. In exchange, Fritzl will be allowed the prison of his choice.

He has selected a “special regime” establishment offering “meditation”, tennis, football and darts. The gym looks better than those of many hotel establishments and Fritzl will be able to sing in a choir. He can also take lessons in cookery.

They could be useful if he is ever granted his wish of returning home one day to live with his wife.

Memoirs up for sale

Fritzl wants to cash in on his worldwide notoriety by selling his memoirs and public tours of the “house of horrors”

He believes he could earn up to £1m for his story and the same for a television documentary about the “beast of Amstetten” that would include exclusive footage from his cellar. He is trying to sell interviews to the press for a similarly astronomical sum.

However, a lawyer representing Fritzl’s children has managed to block a scheme to open the house to the public for £10 a head. Whatever Fritzl earns will go to creditors, who are owed £3.5m.

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