(a)
Notwithstanding Section 42407, any violation of Section 41700 resulting from the engine of any diesel-powered bus while idling shall subject the owner to civil penalties assessed under this article, which may be recovered pursuant to Section 42403 by the Attorney General, by any district attorney, or by the attorney for any district in which the violation occurs in any court of competent jurisdiction.(b)
There is no liability under subdivision (a) if the person accused of the violation establishes by affirmative defense that the extent of the harm caused does not exceed the benefit accrued to bus passengers as a result of idling the engine.
Source:
Section 42403.5, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=HSC§ionNum=42403.5..