Who is responsible for Anders' death in Tobias Wolff's "Bullet in the brain"?

"Bullet in the Brain" by Tobias Wolff is the story of a man named Anders, a book critic, who experiences one final memory after being shot in the head during a bank robbery. Anders, the main character, is presented in most of the story as being a pompous and unsympathetic character. His interactions with the woman in front of him, and his overall critical nature of the world present him as a character who the reader has a hard time caring about. The noticable nonchalant attitude he had towards the bank robbery was an interesting aspect of the story and preludes his rebellious attitude towards the bank robbers. With these initial reactions to the bank robbery, you can begin to see the peculiarness of this character. You wonder if he cares about his own life, if he is even aware of the severity of the situation, or if he even finds these bank robbers to be too predictable in their actions. He critiques them as he would one of the books he reads. He seems unable to censor himself or realize that there is a time and place for everything. Even while he has a gun to his head, he takes time out the moment to critique a mural. He continues to remain defiant up until the very moment he is shot in the head.