The questions to ask depend upon much more facts than you have shared. Call Andrew Roberts, Esquire, an experience traffic ticket attorney who posts here on Avvo quite often. He is really good. He handles cases in LA County such as yours.
If there was just a set script to read from during cross examination to dismiss a ticket there wouldn't be a need for lawyers and everyone would get off. Effective cross examination takes years of experience. If you actually want a shot at getting it dismissed, hire a traffic lawyer.
Each ticket and facts are unique. There is no set list of questions.
ANDREW ROBERTS CRIMINAL AND TRAFFIC TICKET DEFENSE ATTORNEY
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