The source of this dishonesty -- both in Whitman's attack ads and Brown's new ad (above) -- is Prop 13. Its passage by voters in June 1978 led to big cuts in taxes, but also helped turn a big surplus into a deficit. (In fact, the size of the Brown-created budget surplus helped fuel anger at property taxes that in turn fueled Prop 13).
Whitman's ads dishonestly exploit these facts by blaming Brown for the deficit when he left office, which was caused by Prop 13, while not giving him credit for the tax decrease. Whitman is guilty of major-league chutpzah here because she has portrayed herself as a strong supporter of Prop 13.
Brown's ads are dishonest in almost exactly the opposite way. He takes credit for the tax cuts of a measure that he first opposed -- while not ducking responsibility for what it did to the budget. In the ads, Brown is said to have balanced budgets -- which is technically true (he did balance some budgets) and totally misleading.
Of course, none of this back-and-forth about the past matters much since neither candidate, for all their touting of various policy plans, has anything approaching a real plan for California's current political and budgetary crisis. And to the extent, Brown is seeking to capitalize on his past as governor (the ads touts his "knowlege and know-how"), he raises more questions than he answers.
Brown suggests that he would let voters decide on taxation questions, which is precisely what caused the trouble when he was governor before (in 1978). And he promises to restore local control -- which requires reversing some elements of Prop 13, which he has promised not to touch in his campaign.
It's a shame that one of these two candidates has to win.