By Phil Bronstein
San Francisco Chronicle
SAN FRANCISCO — BART Police Commander Dan Hartwig stood in a Walnut Creek gas station as discreetly as he could for a man as tall as Mount Diablo. Square-jawed, buffed, he seemed the icon of the old-school super cop.
He watched stoically as competing rallies across the street argued over the professional soul of his former colleague Johannes Mehserle. The two groups screamed at each other in 90-plus-degree heat, with some nasty insults aimed at the very authority Hartwig represents.
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