Jean-Léon Gerôme, Pollice Verso (Thumbs Down), 1872
This well-known historical narrative painting features two gladiators -- a triumphant murmillo and a defeated retiarius -- receiving the judgement of the Vestal Virgins seated above them. Either the judges felt that the conquered warrior did not put up a good fight, or else they held the common view that a retiarius was an inferior type of warrior and did not deserve to survive, no matter how well he fought.
On hot, sunny days the arena was covered with cloth strips that protected the emperor and Vestal virgins. At some places where the edges of the strips did not meet, beams of sunlight barred the walls and ground of the arena. Most of the audience, however, had to swelter in the direct sunlight.
Gérôme painstakingly researched the historical background for this painting, in order to make the scene as accurate as the best of written histories. The current Wikipedia article on this work, however, sees Pollice Verso in these terms: "The blend of voyeurism and a sense of moral superiority is a specific 19th-century feature" -- a judgement perhaps more reflective of the twenty-first century than the nineteenth.