Worker for the Wizengamot
Tiberius Ogden was a former member of the Wizengamot (described as an elder member), but resigned in protest due to Cornelius Fudge's appointment of Dolores Umbridge as High Inquisitor at Hogwarts School of Witchcraft and Wizardry and the continuing campaign by the Ministry of Magic and the Daily Prophet to discredit Albus Dumbledore and Harry Potter.
The name "Tiberius" is a Roman praenomen, or given name, meaning "of the Tiber" in Latin. The Tiber is the river that runs through Rome. Tiberius was the second Roman emperor, the stepson of emperor Augustus.