, '' said the woman identified only as Christine R. in a Saturday interview conducted and translated by AP . `` He tolerated no dissent , '' Christine R. added . `` Listen , if I was scared myself -- I was scared of him at a family party and I did not feel confident to say anything in any form that could possibly offend him -- then you can imagine how it was for a woman who spent so many years with him . '' Watch what the sister-in-law has to say '' In the televised interview , Christine R. added detail to the bizarre story of 73-year-old Fritzl who was recently arrested and confessed to holding his daughter captive in a dungeon under the home for decades , repeatedly raping her and fathering seven kids -- with six of them surviving . Christine R. also said Fritzl committed an unrelated rape in 1967 , served 18 months in prison for that crime and that her sister continued to stay married to him in a desperate attempt to keep their family together . Recent media reports also claimed Fritzl had been convicted of rape . Austrian police have said
AMSTETTEN , Austria -LRB- CNN -RRB- -- The Austrian who reportedly admitted holding his daughter captive for 24 years and fathering seven children with her will plead insanity , his lawyer said . Josef Fritzl admitted to authorities he raped his daughter and fathered her children . Attorney Rudolf Mayer said he believed 73-year-old Josef Fritzl had a mental disorder , The Associated Press reported . Mayer said someone who was mentally ill `` did n't choose '' to do what police allege he did . Mayer said Fritzl would be confined to a psychiatric institution rather than a prison if he was certified as insane and convicted , AP reported . Police said last week that Fritzl had confessed to imprisoning his daughter in a secret cellar dungeon in his home , fathering seven children with her and burning the body of one who died in infancy in a furnace . Meanwhile , Fritzl 's sister-in-law has said his wife did not know her daughter was held captive in their basement for decades because she had been trained not to ask questions under her husband 's tyrannical rule of the household , . `` He was such a tyrant