midnight and claims that he "heard the kid say to his father, 'I'm gonna kill you'" followed by "a body falling." Furthermore, the neighbor says he saw the boy running out of the building.

Another neighbor who gives testimony claims that she saw the murder take place through the windows of an elevated train passing by. This testimony would contradict the claims of the old man who lives beneath the scene of the murder because the noise of the passing train would drown out the conversation that he claims to have heard between the man and his son.

Juror Nine floats the idea that the old man who claims to have heard the argument and the son's threat is an elderly and overlooked person who needs to be heard and recognized. Juror Nine believes that the man isn't necessarily lying, but he is perhaps is either confused about what he heard and when he heard it or conflating things he saw and heard. The juror raises the question of the man's motivations and suggests that he wants to be thought of as an important part of the case.

The old man is weak and walks with two canes, so it takes him a while to travel from one place to the next. When he gives his testimony, it is also revealed that a thunderously loud train was rumbling by outside. Nonetheless, the old man says that he heard a raucous argument going on upstairs, heard the kid yell "I'll kill you!" and heard what sounded like someone collapsing. He then went to his apartment doorway and saw the kid running down the stairs and fleeing from the house, so he called the police.

Though he begins as the prosecution's star witness, the jurors eventually realize that there are some odd inconsistencies with his story. First, the old man moves slowly; he is weak, elderly, and needs two canes to move from one place to the next. It does not seem possible, then, that he could hear the argument going on upstairs and then rush to the door of his apartment to see the defendant running away. Also, there was a very loud train going by just as everything upstairs was happening. The old man's hearing was already poor, so it seemed highly unlikely that he would hear an argument going on in the apartment above him while the train passed.

Juror Nine suggests that the old man is lonely and feels overlooked, so he presents his testimony as a way to get society to see and acknowledge him.

The jurors examine and question the old man's testimony in scene 6. During the trial, the old man, who lives downstairs from the scene of the crime, testified that he heard arguing coming from the apartment above him, including a threat of murder. He then testified that he heard the sound of someone falling down. Alarmed, he ran to the window down the hall and saw the boy running out of the building. He then called the police.

This testimony makes the old man the prosecution's star witness. It certainly seems like enough information to convict the boy of the murder. However, Juror 8 wonders if the old man's story is accurate. Apparently, the witness was in a feeble state, having suffered a stroke some time earlier. He entered the courtroom walking slowly with two canes. Juror 8 does not think that the old man could have had enough time to make it to the window to see what he claims he saw. To illustrate this, he makes a diagram of the apartment on the floor. Moving at the speed of the old man, Juror 8 takes over 40 seconds to cover a distance that would have needed to have been covered in 15 seconds. Furthermore, the timing of the passing train means that it would have been near impossible for the witness to have heard what he claims he heard.

This presents a major flaw in the witness's testimony. Juror 9 suggests that the old man, feeling discarded by society, might have been inventing facts for attention. He tells the others that

A man like this needs to be recognized. To be questioned, and listened to, and quoted just once. This is very important.

All this introduces reasonable doubt into the old man's testimony. Indeed, it is this weakness in the testimony that finally convinces several jurors to acquit.

After the jurors cloister themselves in the jury room and they take a vote, Juror No. 8 is the only one who votes "Not Guilty." When Juror No. 12 suggests that they convince him, No. 3, a very opinionated and intolerant man, goes over the facts. First, he refers to the neighbor's testimony.

The old man, who lives on the second floor under the room where the murder occurred, has testified that he heard noises that were quite loud coming from the upstairs apartment. To him, there seemed to be an argument going on; then, he heard the boy say to his father, "I'm gonna kill you." Right after this, he heard someone falling; so, he ran to his door to look out, and he saw the suspect running down the stairs and out of the house. After witnessing the boy's running away, the old man phoned the police. When the police arrived, the father was found with a knife in his chest.

This testimony seems rather damning, but it is the perseverance of Juror No. 8 in examining and re-examining the testimony and other facts of the case which lead them to feel that there is reasonable doubt about the son's being the one who stabbed his father. 

The testimony of the neighbor who lived down stairs is based on what the man allegedly heard in the upstairs apartment. He did not actually see the murder. He claims that he heard the sounds of arguing coming from the apartment above, a voice that he presumed was the defendant’s yell out that he was going to kill the other person and then, after going to the window, the neighbor saw the defendant running away.

Juror No. Three summarizes the neighbor’s testimony:

Let's take the old man who lived on the second floor right underneath the room where the murder took place. At ten minutes after twelve on the night of the killing he heard loud noises in the upstairs apartment. He said it sounded like a fight. Then he heard the kid say to his father, “I'm gonna kill you.” A second later he heard a body falling, and he ran to the door of his apartment, looked out and saw the kid running downstairs and out of the house. Then he called the police. They found the father with a knife in his chest.

Juror No. Eight is puzzled by the testimony and says that “It doesn't seem to fit.” He questions whether the neighbor was actually able to get to the door of his apartment in time to see the defendant running away—if, in fact, the defendant was the perpetrator. The timing does not work out; the neighbor probably did not have sufficient time to get from his bedroom to the door, given how far the bedroom is from the front door to the apartment.

Why then would the neighbor testify that he heard and saw what he did? First, the neighbor’s mind could be playing tricks on him. It is quite likely that he was awakened by loud noises and presumed that they came from the apartment directly above his. However, what if the noises came from another apartment? Could the neighbor be certain? In the aftermath of the murder, it is likely that the neighbor superimposed the fact that the father had been stabbed to his recollection of the events. He probably believed that his testimony was unbiased and based exclusively on facts.

However, as Juror No. Eight shows, the neighbor’s recollections of the events on the night in question are not entirely plausible. His subsequent testimony was probably affected by what he read in the papers after the murder.

Moreover, the neighbor is, in all likelihood, a man who is not often asked for his opinion or made to feel important. Testifying in court in a sensationalized crime case probably made him feel important. While he probably did not realize it, it is likely that he embellished his testimony to enhance his own sense of self-importance.