question:  Why doesn't Julia tell the policeman about the bomb?
context: I had finished reading the Chronicle , folded and put it beside me, turned and looked out the window, expecting to see the San Joaquin Valley but finding only a sea of clouds instead. So I returned my attention to the inside of the plane, to the overstuffed gray-haired woman asleep beside me, to the backs of heads in seats before me, across the aisle to other heads, and down to the blonde. Inventory completed, I went back to looking at the clouds, knowing I should be thinking about the printing order I was going to Los Angeles for, and not wanting to. I learned the wisdom of keeping my mouth shut in the fourth grade when Miss Winters, a stern, white-haired disciplinarian, ordered me to eat my sack lunch in the classroom with her instead of outside with some of the other kids. I didn't want her to think I had taken it while she was out of the room, so I probed the contents of her purse, which she always kept in the upper right drawer of her desk. I had set my alarm for five-thirty because I had to catch the seven o'clock plane at San Francisco International Airport. This being earlier than I usually get up, it seems all I did during the night was feel my way past the escapement and balance wheel to see where the notch for the alarm was. The bomb was in a small bag—a woman's bag judging by the soft, flimsy things you'd never find in a man's—and I didn't know it was a bomb right away. One went to a battery and the other to hard round cylinders taped together. Quickly I went up past the train of gears to the alarm wheel. If this was anything like my own alarm clock, this one had something like ten minutes to go. It was forty minutes to Burbank and Lockheed Air Terminal. No, none of them would know it was there. We'd be leaving the valley for the mountain range north of Los Angeles soon, if we hadn't left it already.
output:  She does not want to be blamed for the thief's death.
options:  This is her chance to disappear and start a new life.  She doesn't think the police will believe her husband tried to kill her.  She does not want to be blamed for the thief's death.  She doesn't want the narrator to have to explain his gifts.