aes, "bronze" or "money" in its subsidiary sense of "poll tax") were a class of Roman citizens not included in the thirty tribes of Servius Tullius, and subject to a poll-tax arbitrarily fixed by the censor.
This type of decemvirate (also called the decemviri litibus iudicandis and translated as "the ten men who judge lawsuits") was a civil court of ancient origin (traditionally attributed to King Servius Tullius) mainly concerned with questions bearing on the status of individuals.
The François Tomb also contains a fresco depicting Caelius Vibenna (whom the Romans believed the Caelian Hill was named after) and Mastarna (a legendary figure whom the Emperor Claudius identified with Servius Tullius).
The senate advised the king, devised laws in his name, and was held to represent the entire populus Romanus (Roman people); but it could only debate and discuss.
These Being the Words of Marcus Tullius Cicero | Servius Tullius | Publius Tullius Albinovanus |