Former Officer Johannes Mehserle shot Grant in the back while struggling with him on the platform at Fruitvale Station in 2009. Mehserle claimed he mistook his gun for his Taser.
A jury later convicted Mehserle of involuntary manslaughter for Grant's death.
Monday's vigil was held at the Fruitvale BART Station in Oakland from 12 p.m. until 4 p.m.
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