Attorney Cathy McCulloch had a client who was accused of eight counts of raping his own daughter over a six-year period. The man adamantly denied that he had ever laid a hand on his daughter, but the girl gave a very “compelling interview” to police and shared explicit details of the crime.

The way the girl described the incidents didn’t sit well with McCulloch. She wrote on her UK-based blog that “the use of certain words, phrases, and descriptions of how she felt” seemed well beyond a girl her age. Then a lightbulb went off. Her client mentioned that his daughter’s favorite book was Fifty Shades of Grey, and it appeared that she may have been using material from the book to give her testimony.

There were “too many striking similarities” between the girl’s statement, parts of which “appeared to have been lifted from the book,” according to an instructing solicitor assigned to the case. After picking up a copy of the book, the team found 17 different examples pointing to the racy novel as material for the girl’s accusations against her father.

McCulloch studied Fifty Shades of Grey to prepare for the court proceedings. On the third day of the trial, the man’s daughter took to the stand, and McCulloch used passages from the book to question the girl. After just seven minutes, she broke down and admitted she had made up the accusations to teach her “strict” father a lesson. After the prosecutor re-examined the girl a second time, the father was granted an immediate acquittal.