“He don’t even speak good English” (Situational Irony)
At one point, the bigoted Juror 10 rails against the defendant and the fact that he is foreign and poor. He complains that the defendant "don't even speak good English," which is, of course, ironic, because it is itself not grammatically correct English.
9 notices things (Situational Irony)
Juror 9 is often dismissed and overlooked because he is an older gentleman, and many of the jurors treat him disrespectfully. The fact that people are ageist and dismiss him only makes him more observant. At the end of the film, it is he who notices that the woman who says she saw the murder usually wears glasses and likely could not actually see the event clearly. This is what turns the remaining jurors to say that the defendant is "not guilty."
3 changes his mind (Situational Irony)
After being so bullish and aggressive throughout the deliberation, 3 eventually changes his tune and agrees with the rest of them that the defendant is not guilty. He bursts into tears at the sight of his estranged son and says "not guilty" over and over again, like an inconsolable child.
