James Mattesich has practiced law since 1972. Together with Gene Livingston, Jim founded Livingston & Mattesich in 1982 to represent clients in their interactions with the State of California, and was among the first attorneys in Sacramento to provide experienced and effective advocacy in all forums of public decision-making: legislation, regulation and litigation. Prior to his appointments to his state government positions, Jim litigated at all levels of the state and federal court systems, including the U.S. Supreme Court. He taught trial practice for the United States Legal Services Corporation.

He has combined his insider's knowledge of state government and his knowledge of the Legislature, state agencies, and the courts to the full advantage of his clients. Jim's multidimensional experience enables him to not only respond effectively to the current political and regulatory landscape, but to also anticipate new trends and changes that could affect his clients' goals.

Jim's legislative advocacy practice involves a broad range of regulatory and policy issues, and offers services unique to a lawyer-lobbyist. He combines his understanding of the statutory and administrative law relevant to the specific issue with his familiarity of how the legislature and the regulatory agencies actually work on behalf of each client. Jim can evaluate whether a regulation complies with the underlying law, court decisions and the administrative procedures for adopting regulations. If lobbying and administrative advocacy does not suit the client's specific needs, he can remedy legislative and regulatory problems in the courts.