"The complainant's interview was going to be really tough to crack. She had described not only what her father had allegedly done, but how her body felt as a result.
"The only odd thing was the use of certain words, phrases and descriptions of how she felt which seemed beyond her years."
She said that during a conference with her client he mentioned that his daughter's favourite book was Fifty Shades of Grey, despite him having "no idea" what the 2011 book, which describes a sadomasochistic romance from the perspective of a young woman, was about.
After another member of her team bought a copy of the novel and noticed strong similarities with the girl's testimony, McCulloch asked for the trial to be adjourned so that she could read the book and incorporate it into her defence.
She wrote: "I started my cross-examination gently to put the complainant at ease. She agreed her father was strict, and that she was really annoyed with him for 'ruining her life.'
"I then went straight to my final question - that she was so angry with her father that she had made this all up.
"She wavered. I raised the striking similarities between her interview and the book. She suddenly broke and said I was absolutely right.
"She had made the whole thing up because she was angry with her father and wanted to teach him a lesson."
Fifty Shades of Grey sold more than 125 million copies worldwide and was adapted into a 2015 film starring Jamie Dornan and Dakota Johnson.
