Greek Philosophy 6.2: Owls to Athens 2: The Sophists 

Hi Pamir: One (fun) piece of historical background here is the Athenian legal system. Athens didn't allow prosecutors or defendants to represent a client in court; instead, professional speechwriters (logographoi) would write speeches for their clients to deliver. So, there weren't quite 'lawyers' in a typical modern sense-of barristers. One version of Plato's discussion of this in the dialogue 'Phaedrus', analyzing the difference between writing and live conversation, with reference to the famous logographos Lysias. There's certainly a similarity between the logographos and the sophist, but it's also important to consider that 'sophist' is a category constructed by Plato (and others) for criticism of a group, not necessarily a self-description of that group. Thanks for the good question!