Cherry Believes that Both Gangs Have it Tough (Situational Irony)
When Ponyboy and Cherry go to the concessions stand at the drive-in movie, Cherry makes the observation that things are tough everywhere, whether one is a Greaser or a Soc. She laments that if only the gang members realized this was the case, maybe they could understand each other and stop fighting. This moment is ironic, because it highlights the fact that the violence between the Greasers and the Socs is senseless and unnecessary, but it is also ironic because it highlights Cherry's naïveté about the nature of the rivalry between the two gangs. While Cherry wants to show Ponyboy that both sides have it rough, she doesn't realize how difficult the lives of the Greasers really are, because of poverty and hardship. Socs undoubtedly have difficult lives as well, but the class differences create real tensions. While the issue seems easy to solve to her, the class tensions between the two gangs are embedded in their community and are a reflection of broader economic and socio-political issues, rather than just an arbitrary tension. Her failure to realize this is itself part of the problem: because it's hard for a rich person like her to see why poor and rich, Greasers and Socs can't just get along, the real differences between them go unaddressed, and the problems get worse.
Dallas' Gun is Unloaded when he is Shot (Dramatic Irony)
While the viewer and the other Greasers know that Dallas' gun has no bullets in it at the end of the film when he is apprehended by the police, the policemen have no idea. As a result, they think he is a crazy man waving a gun threateningly, and they shoot him. Dallas dies over a misunderstanding. The dramatic irony comes from the fact that while we the viewers know that his gun is unloaded, the cops have no idea, leading them to misjudge the situation. If the cops knew that his gun was unloaded, they likely would not have shot him. Therefore, a violent and tragic situation might have been prevented if the policemen had more information. Complicating the situation even further is the fact that Dallas is threatening them with his gun as though it is loaded. He puts on a performance to give the cops the impression that he is a violent man, thus encouraging the misunderstanding that ultimately kills him.
Johnny, Dally, and Ponyboy's Heroism (Situational Irony)
Dallas is painted as a delinquent, a loyal but hot-headed and irreverent ne'er-do-well from the start of the film. Later, Johnny kills Bob with a knife and must flee the law with Ponyboy, criminals on the run. When the church burns down, however, Ponyboy, Johnny, and eventually Dallas turn into heroic saviors, seeking to save helpless children from the flames. The Greasers are gang members, hardly local heroes, but their acts at the church propel them to an unexpected ethical high ground. When Ponyboy speaks to the teacher at the hospital, the teacher marvels at his heroism, but when Ponyboy tells him that they are Greasers, he hardly believes him. Thus, there is an ironic dissonance between the boys' status as Greasers and their moral ascendance in the community for their heroic deed. In transcending the typical stereotypes of what it means to be a Greaser in order to do what's right, Ponyboy, Johnny, and Dallas elude expectations. In going in to the burning church, the three boys do what even the children's teachers were unwilling to do.
Johnny's Death (Situational Irony)
Johnny goes through a complicated trajectory in the film. He kills Bob in order to protect his friend, but then must flee the law. Even though he was acting in defense of his friend who was in a vulnerable position, he fears the consequences of his deed. Later, he redeems himself in the eyes of the community by helping to save the children from a burning church, but it ultimately costs him his life. Though in a film about gangs, we might expect that a good turn would lead to a happy fate, it is precisely when Johnny breaks out of the role of violent gang member that he meets his death. While Johnny is only ever trying to do the right thing, he meets a difficult fate at every turn. Initially his heroism in trying to save his friend results in his being charged with manslaughter. Then later, his heroism in trying to save the children turns to martyrdom. Johnny is only ever trying to do the right thing, but in the end, he dies.