This building has been called palacium ubi ius redditur, which is Latin for ‘place where justice is administered’ since 1311 and has been used to the same purpose throughout.
The Lombard band with hanging arches discovered once the heavy coating of plaster was removed probably belongs to the original building, possibly constructed during the second half of the 13th Century. The plaster had in fact blotted out all traces of earlier structures as well as the richly painted decoration on the other facades of the building.
The original medieval structure was first rebuilt in 1462, when Guglielmo Casatroia, on behalf of Marquess Giovanni I, entrusted the reconstruction of the palazzo to maestro Giorgio Molinaro de Plebe.
The lunette with the Four Cardinal Virtues in Finale stone dated 1462 and the image of the robed Judge and the cartouch ‘Nichil utille nixi sit honestum, literally ‘Nothing is useful if it is not honest’ were all refurbished at this time.
On the ground floor, the medieval palazzo opened up into a loggia with linteled windows supported by small, slender central columns, which are still visible on the façade.
The richly painted decorations belonging to the end of the 15th and the beginning of the 16th Centuries are exceptional with a fake red and green truncated pyramid rusticated ashlar-work criss-crossed by bands with a spiralling pattern of mottos alluding to strength and rightfulness with images of leaves and cherubs.
The facade was mostly restored in 2011.
A loggia with terracotta frieze of garland-bearing cherubs lies to the left and is visible from the gate that leads to Castel San Giovanni.
The building was used by the Spanish governors from 1625 and later on, after 1713, by the Governors of the Republic of Genoa.
Interior re-decoration and refurbishing were carried out when Infanta Margaret of Spain stayed at the palazzo in 1666 before travelling on to Vienna.
In 1789, Benedetto Andrea Centurione, the Genovese governor of Finale, pressed for a further refurbishment of the building, as confirmed by the long frieze across the front.
The main facade was enlarged, blocking the medieval loggia from sight and a new central entrance was opened up featuring a lintel with military motifs together with the rounded abutments of a 16th-century fireplace recycled from Castel Gavone. The allegorical painting around the portal dates back to the Napoleonic period.
The present-day place was built in 1782, when the so-called “Casa del Cancelliere”, or ‘Chancellor’s house’ was knocked down. Palazzo Cremata looks out over the east side of the square, while Palazzo Arnaldi faces onto the west. Some graceful stucco decorations from the 19th Century frame the windows on all floors.