A cardinal sits in a red velvet chair decorated with gold braid. One of his hands lies on the arm rest, the other holds his cardinal’s biretta (hat) on his knee. Behind him is a bookcase, the shelves of which are lined with very large leather-bound volumes. The sitter is identified by the inscription along the spines of the books as Carlo Cerri (1611--1690), Dean of the supreme ecclesiastical tribunal, or 'Rota'. The Rota is the highest ecclesiastical court set up by the Holy See for judicial trials in the Catholic Church. Cerri was created Cardinal, Bishop of Ferrara and Legate of Urbino on 29 November 1669 by Pope Clement IX. The portrait was probably painted soon after this date, but before 1679, when Clouwet, who made an engraving of the portrait, died. The inscription on the books refers to Cerri's most important work, the Decisiones Rotae (Judgements of the Rota).