OAKLAND -- An arbitrator today overturned BART's firing of Marysol Domenici, a police officer who had been accused of lying to investigators and an Alameda County judge about another officer's killing of unarmed train rider Oscar Grant. Although BART never accused Domenici of using excessive force, she became a focus of some of the community outrage stirred by the case because she helped detain Grant before he was shot by former Officer Johannes Mehserle. A jury convicted Mehserle in July of involuntary manslaughter for the Jan. 1, 2009, killing at BART's Fruitvale Station in Oakland. He was sentenced to two...