The interpersonal communication going on in the room is mainly between the jurors that say the boy is guilty and the ones who say he isn't. The tension in the room mainly come from juror 8, which we find out is mr. Davis at the end of the film, and juror 3. These two are kind of like the heads of the guilty and non-guilty parties.
Juror 8 used mainly two types of appeals to convince the other jurors. He used the ethical appeal when he explains to the jurors that the boy didn't mean it when he said he'd kill his dad because we've all said that we would have killed for this or something like that when we don't really mean it. Juror 8 uses logical appeal when he explains to the jurors that the man couldn't have seen the boy run down the stairs because it would have token him longer to get to the stairs from his bedroom considering that he was hurt at the time.
In this movie, some jurors are easy to convince that the boy is non-guilty and some are very difficult. They are difficult to convince for two reasons, one, the boy seems like a bad kid when he was being testified in the courtroom, and two, one of the "Nay Sayers" which was juror 3, the antagonist, has a background with his own kid which wasn't too great. The jurors who plead guilty mainly used one appeal which was the ethical appeal. One juror used logical appeal by saying that an old lady saw the boy run out of the apartment building, but it turns out that it could have been anyone because she didn't have her glasses on.
I really enjoyed watching this film. It portrays how all appeals are used in speeches. The only thing that I didn't like about it was that it didn't tell who killed the man.