Audit Oversight Committee Voting Members


CPA
AOC Vice Chair
Private Sector Member, 2nd District
Tim Johnson is a founding partner of JLK Rosenberger, a CPA firm heardquartered in Irvine. He has over 25 years of broad public accounting experience and extensive expertise in tax planning, consulting, and compliance for high-net-worth individuals and various industries, including professional athletes, manufacturing and distribution, healthcare, and real estate.
He earned a Master of Science in Taxation from Golden Gate University and a Bachelor of Science from California Lutheran University.
In addition to his role on the Orange County Audit Oversight Committee, Tim is the Finance Chair for Good Shepherd Lutheran Church, and the Santa Ana Measure X Oversight Committee Chair.
Private Sector Member, 4th District

Private Sector Member, 1st District
Drew Atwater is the Director of Finance and Water Resources at Moulton Niguel Water District, overseeing the finance, water efficiency, and water resource planning departments. Drew has overseen the integration of District analytical talent across disciplines to create an interdisciplinary data science and quantitative team to improve efficiencies throughout the agency. Mr. Atwater has a Bachelor of Arts in Physics from Reed College and a Masters in Science in Environmental Science focusing in Environmental Economics and Policy from the University of California at Riverside.

Interim County Executive Officer
Member

CPA
Private Sector Member, 3rd District
Mark F. Wille earned his CPA in 1977 while employed by Arthur Andersen & Co. as an audit and tax accountant. He later joined one of the largest Southern California commercial real estate brokerage firms as vice president of finance.
In the mid 80’s, Mr. Wille started a private practice specializing in small business and real estate, providing professional services in financial, accounting and tax-related areas. He also worked on large public company purchases of small businesses.
Mr. Wille is a CPA firm peer reviewer for the American Institute of CPAs. He is former chair of the California State Accounting Principles and Auditing Standards Committee and a current member. He is former chair of the Audit Oversight Committee for the County of Orange, the sixth largest county in the United States. Mr. Wille teaches continuing education courses for CPA’s.
He has taught college business courses and frequently lectures to business and civic groups. On the personal side, he is an Eagle Scout and is active with the Orange County Boy Scout Council and served on a National Committee of the Boy Scouts of America. He has earned a master’s degree in theology from Fuller Theological Seminary.
Mark joined JLK Rosenberger in 2022 where he provides substantial strategic planning and financial coaching to small business clients. He also consults with CPAs regarding various accounting and auditing matters, provides practice management, peer review, performs peer review inspections, and assists CPAs in the sale of their practices.
AOC Chair
Private Sector Member, 5th District