The Outlaw's Tale by Margaret Frazer

This mystery builds slowly, and relies on Dame Frevisse's ability to read character as much as her ability to read clues. Although she's outside of the convent when she's waylaid by her long-lost cousin, an outlaw, she still has severe limitations on the amount of direct detecting she can do. Not my favorite of this series, but a very nice portrait of medieval life in a well-to-do household.