Gaius Trebatius Testa was a jurist

Jurist

A jurist or jurisconsult is a professional who studies, develops, applies, or otherwise deals with the law. The term is widely used in American English, but in the United Kingdom and many Commonwealth countries it has only historical and specialist usage...

 of ancient Rome

Ancient Rome

Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

, whose family, and himself, originated from Elea.

He was a protege of Cicero

Cicero

Marcus Tullius Cicero , was a Roman philosopher, statesman, lawyer, political theorist, and Roman constitutionalist. He came from a wealthy municipal family of the equestrian order, and is widely considered one of Rome's greatest orators and prose stylists.He introduced the Romans to the chief...

; Cicero dedicated his Topica to Trebatius, and recommended Trebatius as a legal advisor to Julius Caesar

Julius Caesar

Gaius Julius Caesar was a Roman general and statesman and a distinguished writer of Latin prose. He played a critical role in the gradual transformation of the Roman Republic into the Roman Empire....

. Trebatius enjoyed Caesar's favor, and later that of Augustus as well.

Trebatius' writings included a de religionibus and de iure civili, but not even excerpts of these survive. He was, however, frequently cited by later jurists, and also had a high reputation as the teacher of Marcus Antistius Labeo

Marcus Antistius Labeo

Marcus Antistius Labeo was a prominent jurist of ancient Rome.He was the son of Quintus Antistius Labeo, a jurist who caused himself to be slain after the defeat of his party at Philippi...

.