When Assemblyman Jim Frazier, D-Oakley, state Sen. Bill Dodd, D-Napa, and other legislative colleagues came to Walnut Grove for their first Delta Caucus investigating the finances of Gov. Edmund Brown Jr.’s twin tunnels plan, they were well prepared. They brought four state auditors and an economist, Jeffrey Michael, director of the Center for Business and Policy Research at the University of the Pacific in Stockton.