A video image from a Taser shows Tanner Chamberlain, 15, holding a knife near his mother, Evie Oquendo, seconds before the teen was fatally shot by police

Las Vegas police officer Derek Colling faced a packed courtroom Friday and stoically explained his decision to shoot a 15-year-old boy in the head on Sept. 29. ... Colling said the boy, who suffered from a mental disorder, left him with no other choice when he held a knife to his mother's throat and ignored commands to drop the weapon. ... "I did what had to be done," the officer testified at a coroner's inquest. "He placed me, he placed all of us in that situation." ... Seven jurors agreed and unanimously ruled the shooting justifiable.

Clark County might sue online travel companies such as Expedia and Orbitz for unpaid room taxes that one attorney said could total $200 million to $500 million.

If the Southern Nevada Health District made H1N1 vaccine available to people 25 to 64 with certain chronic health conditions, a high-risk group for swine flu, the supply could be depleted before many children could be vaccinated.