SOLVED. Adult Sci-Fi: scientist's daughter has brain tumor, he believes she can cure herself with her mind. The courts disagree, so she undergoes surgery which the father believes destroys her consciousness, so he kills her. A courtroom battle ensues. [s]

[Jack]

Science fiction, set in the United States probably in the 70's or 80's.
The main character, a male scientist, has trained his daughter (who is maybe 10 or 12 years old) to be a genius and to consciously control things like her blood pressure. She is taken to the doctor and is found to have a brain tumour. She is able to cut off the blood flow (?) to the tumour using her training, so the father does not want her to undergo potentially dangerous surgery. The doctor and child welfare services (or equivalent) disagree, and the operation is done against the father's will. It seems to be successful, but the father believes she is now essentially a zombie, with none of her previous intelligence or personality traits, and in his eyes his daughter is dead. To illustrate some point, he gives his daughter a gun and tells her to shoot herself, and she does (the doctor witnesses this).
The remainder of the novel is mostly a courtroom drama in which the nature of intelligence and life is debated. At one point a flight attendant is brought in as a character witness to testify about the father preventing a hijacking attempt on an airplane. As well a trained chimpanzee, which I think has some grasp of sign language, is brought in to court and killed to prove some point about the true nature of intelligence/consciousness. This upsets the judge. Ultimately the father is found guilty, and I believe is sentenced to death.
The book ends with a police investigator (or maybe the defense lawyer?) going to the scientist's home, which has been rigged up with smart computer systems (which can for example recognize visitors and open the door), and finding his laboratory in which he has created robots which contain his and his daughter's consciousness.
The author is male, I believe he was the founder of some cult-like group which has some strange ideas about consciousness.
I read the book in 2019 (found in a little library), likely published in 1970-1985. It is a paperback maybe around 200 pages.
The cover shows the scientist father looming over and controlling the daughter (who looks like a zombie) like a puppet master. The cover is in the typical "bad retro sci-fi paperback book cover" style. The link below shows a mock-up of what I think it roughly looked like. I think the word "daughter" may have been in the title.

Any ideas would be appreciated!

Book cover mock-up:
https://drive.google.com/file/d/1y_66...

[Becca]

This has to be The Soul of Anna Klane by Terrel Miedaner:

Your mock-up is brilliant - you even got his beard!

[Jack]

That's it! Thanks so much!