Oscar Pistorius was charged with murder after shooting his girlfriend in their home . The South African athlete is accused of killing Reeva Steenkamp on Valentine's Day last year by firing a single bullet through the door and window before fleeing to safety. He says living behind high walls changes people 's mindset about security . Irwin : ( CNN ) -- Residents tend to be more careless and casual when they live in a maze of concrete .
Oscar Pistorius was charged with murder after shooting his girlfriend in their home . The South African athlete is accused of killing Reeva Steenkamp on Valentine's Day last year by firing a single bullet through the door and window before fleeing to safety. He says living behind high walls changes people 's mindset about security . Irwin : Residents tend to be more careless and casual when they live in a maze of concrete .