Dash Butler, the Berkeley police chief who retired in 2002, will serve as interim BART oberfuhrer while the embattled transportation system looks for someone more permanent. He replaces Gary Gee, who never recovered from the fatal shooting of Oscar Grant by BART cop Johannes Mehserle on New Year's Eve last year. But BART officials may want to pay attention to whatever contract they signed when they hired Butler. As this paper reported in the antediluvian age, Butler was careful to postpone his Berkeley retirement date for one year, at which point the City Council stupidly agreed to a new deal that gave him an additional $46,588 in annual retirement benefits. Butler was a pretty good chief, but he was clearly better at gaming the pension system. Caveat emptor, is all.