Meletus was probably a poet by trade and likely a religious fanatic who was more concerned with allegations of impiety than with the charges of corruption that were lodged against Socrates. Some believe Meletus was motivated primarily by the reports that Socrates had embarrassed the poets (in Plato's Gorgias, Socrates accuses poets and orators of flattery and says that they impress only women, children, and slaves).
In the Euthyphro, Plato describes Meletus, the youngest of the three accusers, as having "a beak, and long straight hair, and a beard which is ill grown." Plato wrote that, prior to the prosecution of Socrates, Meletus was "unknown" to him. During the first three hours of trial, Meletus and the other two accusers each stood in the law court in the center of Athens to deliver previously crafted speeches to the jury against Socrates. No record of Meletus's speech survives.
However, we do have Plato's record of Socrates's cross-examination of Meletus (in those days, the defendant always cross-examined the accuser). Using his trademark Socratic Method, Meletus is made to seem an inarticulate fool. He says that Socrates corrupts the young, and that Socrates is the only one to do so, but he can not provide a motive for why Socrates would do this. Socrates shows that if he were to do this it must surely be in ignorance, for no man would intentionally make bad those living around him. Concerning the accusation that Socrates believed in strange spirits and not the gods of the state, Socrates tricks Meletus into saying that spirits are the offspring of gods, and since no one believes in flutes playing without flute players, or in horses' offspring without horses, how could Socrates believe in the offspring of gods without believing in gods? For much of his cross examination Meletus remains silent, and we are led to believe that he does not have ready answers for Socrates.
Greek historian Diogenes Laertius, writing in the first half of the 3rd century BC, dubiously reported that after the execution of Socrates "Athenians felt such remorse" that they banished Meletus from their city.