Suicide -- spoiler if you haven't finished the book
Did Alaska commit suicide? I don't think the Colonel and Pudge and Takumi know whether she did or not. Students discussing the book at North Country did not come to a conclusion. They agreed her death was unfortunate and felt her friends should have stopped her from driving, but they felt she did not intend to commit suicide when she left the school. Unless -- at the very last moment she made a split decision not to put on the brakes or swerve, but, then again, maybe she thought she could make it past the police car and did not want to be delayed on her way to her mother's grave.

