Minette Walters - The Sculptress

Probably her best book. Edgar Award winner. Really well done exploration of how people are damaged why they confess. Also, how certain personality types can manipulate others.

Book description

Convicted of the brutal ax murders of her mother and sister, Olive Martin spends her days in prison carving tiny human figures out of wax. Rosalind Leigh is a best-selling author whose publisher jolts her out of writer's block by telling her to research a book about Olive and the murders, or else. Though repelled by the idea at first, Rosalind soon becomes intrigued by her subject and begins to believe she may be innocent. She soon uncovers plenty of reasons to doubt the official police version of the killings and with Olive's help, untangles a sinister cover-up.