A particular moment occurs when everyone else is prattling on how the boy's switchblade was damning evidence since it was unique. Juror #8 silently destroys that argument with one blow when he produces an exact copy of the switchblade and stabs into the table.note Of course, in real life, since he went out and bought it specifically for the next day's deliberation, that would end the case in a mistrial.
He gets another just a few minutes later. One argument in favor of conviction was that the defendant was heard yelling, "I'LL KILL YOU!" at the victim. Juror #8 provokes Juror #3 (the one most adamant for a conviction). Juror #3 lunges at Juror #8 and has to be held back by the others as he yells, "I'LL KILL HIM! I'LL KILL HIM!" Juror #8 stays calm and cool, and says in an almost mocking voice, "You don't really mean you'll kill me, do you?"
Gets yet another one when #3 is holding the knife to reenact the stabbing. When everyone freaks outnote Likely thinking that, due to the fighting between the two, #3 might really stab him, he doesn't even bat an eyelid.
They all got a collective moment when they reject the racist rant of Juror #10 toward the end. As one by one they all turn their backs to him, he grows more and more distressed, bewildered by their rejection of his words, until the only man still facing him is the stoic businessman, Juror #4.
Juror #10: Listen to me. Listen.
Juror #4: I have. Now sit down and don't open your mouth again.
And, for the rest of the movie, that's what he does.
Juror #4 gets another one towards the end when he calmly, rationally (in stark contrast to #10) explains why he still thinks the boy is guilty, and is so convincing he actually swings a not-guilty voter back to guilty (albeit temporarily) — the only time that happens.
And another when everyone else is succumbing to the heat of the room.
Juror #5: Pardon me, but don't you ever sweat?
Juror #4: No, I don't.
Topped later when his argument falls apart and he wipes his brow for the first (and only) time.
Juror #9 gets two. First, when #8 offers to change his vote to guilty if all eleven other jurors still vote that way. #9 votes not guilty, not because he's been convinced of that but because he admires #8 for standing alone in his convictions for so long. Then at the end of the film, he's the one who figures out the critical flaw in the most damning piece of evidence against the defendant. When #3 asks why the defense attorney didn't bring it up, #8 points out that of the twelve of them, eleven couldn't think of it either, and gives #9 a congratulatory back slap.
Juror #11 gets one when Juror #7 changes his vote to "not guilty" just because he is tired and bored and generally "had enough". Right then #11 (who already voted "not guilty') berates #7 violently for not taking the matter seriously:
Juror #11: If you want to vote "not guilty" then do it because you are convinced the man is not guilty, not because you've had enough. And if you think he is guilty then vote that way! But don't you have the guts to do what you think is right?
To show just how disgusting this was, #11 doesn't press the issue when #7 openly insults him for being an immigrant, but he gets pretty pissed over this.
Juror #11 gets another one:
Juror #11: Beg pardon...
Juror #10: "Beg pardon"? What are you so polite about?
Juror #11: For the same reason you are not— it's the way I was brought up.
Juror #6 gets one after Juror #3 was berating Juror #9 over an explanation.
Juror #6: What are you talkin' to him like that for? Guy talks like that to an old man really oughta get stepped on, you know. You oughta have more respect, mister. If you say stuff like that to him again... I'm gonna lay you out.
Juror #5 plays a huge part in proving the knife plot point through is own experience with it. He's also the first to stand up to Juror #10's racist filibuster by slamming down the newspaper and walking away (although technically Juror #3 has already stormed away from the table in annoyance when nine jurors vote for acquittal just before #10's rant begins).
Just before that, Juror #8 standing still to let Juror #3 demonstrate the Reverse Grip's feasibility - by making every motion up to stabbing him - deserves at least an honorable mention.
At the end of the movie, Juror #8 and Juror #9 shake hands and introduce themselves. It is only at this point that you realize you never knew their names... and it doesn't matter.
When Juror #3 gets trapped in his own arguments:
Juror #3: What about all the other evidence? What about all that stuff, the, the knife, the- the whole business!
Juror #2: Well, you said we could throw out all the other evidence!
Also, this beautiful piece of irony (keep in mind that Juror #11 is the only foreigner on the jury):
Juror #10: Bright? He's a common, ignorant slob. He don't even speak good English!
Juror #11: He doesn't even speak good English.
Another (minor) #8 moment, when everyone was trying to prove to him the boy was guilty. Specifically when #10 was explaining the witness's story (seeing the killing from the other side when an L-train passed by).
Juror #8: I'd like to ask you something. You don't believe the boy's story, how come you believe the woman's? She's one of them too, isn't she?