People on this board are overthinking the ending (spoilers, obviously)
There are a lot of posts on this board wondering just what happened at the end. Frankly, this was the clearest and most unambiguous part of the film. But I think that since some of Kitano's films are so cloaked in symbolism and ambiguity, challenging the viewer to think and interpret for him/herself, it's given a lot of his fans a tendency to overthink the obvious sometimes. It was painfully clear what happened at the end. Nishi shot his wife and then himself. There was no ambiguity, no room for uncertainty.
Some posters have put forth the theory that he actually shot the cops. But what would he gain from that? First of all the cops were his friends, some of the only people in the film for whom he seemed to have affection. Why kill them, his friends, so he could end up wracked with even more guilt? And if he killed them to escape with his wife, what good would it do? His wife was on the verge of death, and his own life was now ruined because he had robbed a bank and killed those yakuza. If he killed the cops, he might gain a few days' respite before either new cops tracked him down and arrested him, or new yakuza tracked him down and killed him. Either way, his wife would then be left by herself to die alone, now dealing with heartbreak in addition to leukemia. First she loses her daughter, then her husband too? Nishi obviously cared too much about his wife to do that to her. Everything he had done for her up to that point, all the extreme measures he had taken to take care of her, and the trip he took with her so she could enjoy the last weeks of her life, would be rendered pointless.
Nishi chose that moment for himself and his wife to die because there was nowhere left to go at that point. His wife was nearing the end of her life from the disease. He had gotten into trouble with the yakuza, robbed a bank, and then killed some of the goons who were chasing him, effectively ending his own life. At that point he was on borrowed time, either as a free man if the police caught him or as a living man if the yakuza caught him. But he didn't care, because everything important to him was already going away anyway. He had already lost his daughter, his partner, and he was about to lose his wife. So he decided to make the most of the little time he and his wife both had left by taking her for a trip on the stolen bank money. He did that, and then time ran out. First the yakuza caught up with him, then the police. Presumably he had run out of the money too (since he was unable to pay the interest on his debts). Since things could only go downhill from there, he decided to go ahead and end it in that peaceful moment on the beach, so his wife could die happy with her husband instead of heartbroken and alone, and so he could die with her instead of spending the rest of his now-empty life pointlessly in prison.
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