In act 2 how is irony used in this act ?

Irony is used when two of the jurors play tic-tac-toe; it is ironic that they think of playing games when, in fact, they are deliberating about the life of another human. It is ironic when Juror 3 accuses the other jurors of changing their votes, when it seems like all he wants to consider is that they get this done quickly and get the vote decided. Yet Juror 3 gets so angry he gets completely off track and threatens to kill one of the other jurors. It is ironic that he would act that way, when they are arguing about the life of another human being.