wiki has it a bit more clearly
http://gw.gamewikis.org/wiki/Trial_by_Fire
Summary
Present charges against Kourna.
See Castellan Puuba for your reward.
Obtained From
Jerek in the Plains of Jarin
Requirements:
The Iron Truth
Reward
1,500 XP
250 Gold
15 Sunspear Promotion Points
Dialogue
General Morgahn has arrived from Kourna. Let me tell how the tribunal will go. You will stand, alone, before twenty-two individuals; eleven from Kourna and eleven from Istan. They will ask you a series of questions and allow you to call people to present statements on your behalf. During the testimony, the tribunal members will be able to cast votes to resolve the truth of the matter. Once you are ready we will head there immediately.
Reward Dialogue
The clouds of war are gathering. Yet, if we don't wish to be dominated by the Kournans, so it must be. Come, we have much to attend to.
Followup
War Preparations (Recruit Training)
War Preparations (Wind and Water)
War Preparations (Ghost Reconnaissance)
[edit]Walkthrough
After you speak to Jerek to take the quest, he will ask if you are ready to go to trial. Once you say you are ready, you will be separated from your party and taken to the Tribunal.
In the Consulate, you will find the heroes brought as witnesses (except Tahlkora). The flow of the trial is that you first speak to Elder Suhl to introduce a witness who gives their testimony, then you speak to General Morgahn and answer a question he poses to you. There is a panel of 11 Kournan nobles and 11 Istani nobles. Your objective is to sway them to your side.
The key to scoring well in the trial is to introduce witnesses that coincide with the question that Morgahn is about to ask. This of course is impossible without at least going once through the quest because you introduce witnesses first, then answer questions, certain answers give the best reaction from the jury.
Morgahn's questions will be about:
What happened in the ruins of Fahranur.
The conflict with the Corsairs.
Are you at peace or war with Kourna.
Here is what each witness has to say:
Dunkoro: Provides a well-stated testimoney about the horrors encoutered in the ruins of Fahranur and his opinion as a monk as to the evil that was present there.
Ironfist: Will state that his Corsairs were funded by an unknown Kournan source for some time.
Koss: Doesn't really have much to say, so he makes stuff up about his "sources" telling him that the Corsairs are funded by the Kournas.
Melonni: Provides a very opinionated testimony as to Varesh Ossa's character.
Tahlkora: Will be unavailable during the trial.
As such, the highest score can be achieved by introducing Dunkoro, then Ironfist then Melonni.
The answers that give the best scores to the questions above, are:
Without us Apocrypha would have killed hundreds of people.
We stopped the next Corsair invasion.
We are at peace with Kourna.
Note that during the preview event, this did not result in a different outcome in terms of either the quest reward or the cutscene and the events that unfold afterwards
port