The San Francisco Chronicle has a thorough and unpleasant roundup of how BART officials botched the investigation into officer Johannes Mehserle’s fatal shooting of Hayward resident Oscar Grant. No one among the BART cops present that night reported an officer-involved shooting over their radios, and BART employees shunted a train full of witnesses off before anyone could start asking what happened. BART police had a copy of the cell phone video in which officer Tony Pirone spontaneously punches Oscar Grant, but did not begin an investigation into Pirone until KTVU aired the video. Now, BART officials have handed the investigation over to an outside consultant, a tacit admission that they’re not capable of doing the job themselves. Some BART directors have called for Police Chief Gary Gee and General Manager Dorothy Dugger to step down over the incident. It’s a real mess.