question:  Why did the tear gas that the police were using on Mr. Higgins not work to run him out of the house?
context: There was Mr. Featherhall at his desk, refusing to okay a personal check from a perfect stranger. There was Mrs. Dolly Daniels, withdrawing money from her savings account again. One of the others took the pistol away from Mister Anderson, the guard, and said to him in a low voice, "Think about retirement, my friend." The third one, who carried a black satchel like a doctor's bag, walked quickly around behind the teller's counter and started filling it with money. The man who had first spoken herded the tellers, Mr. Featherhall and the customers all over against the back wall, while the second man stayed next to Mr. Anderson and the door. Meanwhile, Mr. Anderson went scooting out the front door and running down the street toward the police station in the next block, shouting, "Help! The man with the satchel came running around from behind the counter, and the man by the door tried to keep Miss English from scratching his eyes out. She fell unconscious to the floor, and all three of them ran out of the bank to the car out front, in which sat a very nervous-looking fourth man, gunning the engine. Two police cars came driving down the block and a half from the precinct house to the bank, and the car with the four robbers in it lurched away from the curb and drove straight down the street toward the police station. The police cars and the getaway car passed one another, with everybody shooting like the ships in pirate movies. Except that in the trunk lid the owner had burned in 'The Scorpion' in big black letters you could see half a block away." On the way around, Stevenson said, "I believe you reported the car stolen almost immediately after it happened." "If I'm making just a quick stop—I never spend more than five minutes with any one customer—I always leave the keys in the car. "It was four professional criminals, I thought you knew that.
output:  The windows were either broken or open and he was able to throw them back out.
options:  He was unaffected by the gas because of his deranged mindset.  The windows were either broken or open and he was able to throw them back out.  Higgins was too preoccupied by the burns on his hands to care about the tear gas.  Higgins was hanging out the windows shooting and was able to breathe fresh air.