Attic Orator Rhetoric

The Attic Orators were professional speech makers that they had three types of speeches, which were the forensic one about lawsuits, the deliberative one about an effort to convince the Assembly, and the epideictic one about praise or blame of an individual. The speakers had a perfect rhetoric, and the types of the oratories had a foundation of rhetoric that the audience were influenced by them. Through the feature of rhetoric, the audience were convinced by the speakers and their speeches, but were the subjects and/or claims of the speeches true and/or reflect the truth? It might be true or false, or maybe fake. Because of another feature of rhetoric, the speeches were perceived with suspicion. Because of this, historians did not mostly rely on the Attic oratory. The information through the Attic

The defendant might have been right, so this oratory might be unfair against the defendant.
The other example is about epideictic oratory below:

You will see, then, that Timarchus cannot blame the city for any part of this prosecution, nor can he blame the laws, nor you, nor me, but only himself. For because of his shameful private life the laws forbade him to speak before the people, laying on him an injunction not difficult, in my opinion, to obey—nay, most easy; and had he been wise, he need not have made his slanderous attack upon me. I hope, therefore, that in this introduction I have spoken as a quiet and modest citizen ought to speak.

Aeschines gave the speech against Timarchus to blame Timarchus himself, not anyone else. This might have been false and even slander, too.
Since rhetoric speeches might include slander, personal selfishness, unfairness, being one-sided, false claim, and ill things, historians should carefully evaluate them to do