how does Rose meintane doubt as to the defendents guilt or inocent throught the play?

Justice

At the onset of the play, we learn from the Judge's offstage opening instructions the given circumstances of the play, that a man has been accused of murder and his fate is to be determined by these jurors. Immediately, we are launched into a world where the ultimate objective is to complete the "grave responsibility" of determining a man's innocence and guilt, the heart of the American justice system.

Throughout the play, we see two opposing views of justice. From 8th Juror and others, as they join, we see a perspective of justice that favors the accused and that wants most for him to have a fair shot. To 8th Juror, the boy's poor and troubled upbringing, his shoddy state-appointed defense attorney, and the jury's quick near-decisive decision to convict him are all gross forms of injustice.

Conversely, we see another side of justice proposed by the other members of the jury, who feel that the accused is clearly guilty, and anything other than conviction and execution is short of justice. 6th Juror articulates this most clearly, saying, "Suppose you talk us outta this and the kid really did knife his father?" This type of justice depends on retribution and vengeance. Rose plays off the two-sided nature of justice to create tension and contrast the characters. Each character wants "justice," but what justice becomes unclear and fluid throughout the course of the play.

Doubt

What's really interesting about the case within 12 Angry Men is that we never ultimately find out for sure whether the accused is guilty or innocent. While much of the evidence is aptly questioned and manipulated by 8th Juror, at the end of the case there remains a tremendous amount of evidence built up against the accused. Still, it is "beyond a reasonable doubt" that the jurors must find the accused guilty in order to convict him, and they all ultimately come to the conclusion that they have at least some doubt. We leave the play with a sense that justice and right has prevailed over irrationality and prejudice, but, pointedly so, we never actually find out the truth. This doubt over who is on the "right" side pervades the psychologies of the characters in the play and any audience watching.