Caroline, who is based in the United States for The Weekly, won the non-fiction category for her true crime book, Last Woman Hanged.

The book tells the harrowing true story of Louisa Collins, who was both the first and the last woman hanged at the notorious Darlinghurst gaol.

The execution of Louisa, mainly on the evidence of her 10-year-old daughter, galvanized Australian women to campaign for civil rights, including the right to vote and to sit on juries.

Caroline told The Weekly: “I couldn’t be more ecstatic. I’ve watched the Davitt award ceremony for years, never dreaming that I might one day win it. I’m so passionate about Louisa’s story and I really hope the prize encourages more people to pick up the book and learn about her role in the history of our great country.”

As part of her research, Caroline tracked down Louisa’s descendants, none of whom had any idea about the skeleton hidden in their family’s closest. The Thompson family and the Civill family, who live around the Newcastle area, are now campaigning for a memorial for Louisa, who was buried in an unmarked grave at the Rookwood cemetery.

Caroline’s mum, Katrin Schwab, who edited the book, collected Caroline’s prize at a gala dinner in Melbourne on Saturday night.

Other winners on the night included the New York Times bestselling novelist, Liane Moriaty, for her blockbuster, Big Little Lies, which has sold more than one million copies in the United States.

Nicole Kidman has optioned the book, with the aim of turning it into a film.

The Davitt awards are presented by Sisters in Crime. They are named in honor of Ellen Davitt (1812-1879) who wrote Australia’s first mystery novel, Force and Fraud, in 1865.

An e-book of Force and Fraud has just been published by Clan Destine Press.

Other prize winners on the night included Ellie Marney in the best young adult novel category, for Every Word, while Best Children’s Crime Novel went to Judith Rossell, for Withering-by-Sea; and Christine Bongers of Brisbane won the Davitt for best debut, with Intruder. Sandi Wallace’s Tell Me Why also won the reader’s choice category.