Killing Orders: V.I. Warshawski 3 by Sara Paretsky
Years ago V.I. Warshawski's Aunt Rosa treated the detective's beloved mother in an unforgiveable way. Now, after she's accused of stealing $3 million from the Dominican priory where she works, Rosa calls upon the ties of blood to clear her name.
V.I. is not prepared to forgive so easily. Until suddenly no one else - the FBI, a threatening phone caller, and even Aunt Rosa herself - appears to want her on the case either. V.I. turns to an old friend for help. But the stakes are higher than she could have realised . . .