A Professor, Tax Law Leader, and San Diego Community Advocate

Ronson J. Shamoun serves as an adjunct professor at the University of San Diego School of Law and the University of San Diego School of Business, where he teaches courses such as Tax Practice and Penalties and Federal Tax Procedures and Policies. Drawing from more than two decades of real-world experience in complex tax controversy and criminal tax defense, Mr. Shamoun brings practical insight into the classroom, bridging theory with real-life application. In addition to teaching, he serves on the USD School of Law Board of Visitors and the USD School of Business Board of Advisors, and he is a committed supporter of student success through scholarships and mentorship, helping shape the next generation of tax and business professionals. Ronson is a professor, tax law leader and San Diego community advocate.

Tax Law Leader

When clients walk through the doors of RJS LAW, they are not just hiring a tax attorney; they are placing their trust in a firm shaped by the vision, discipline, and integrity of its founder and CEO, Ronson J. Shamoun. For more than two decades, Mr. Shamoun has built a reputation as one of California’s most formidable advocates in tax law, guiding individuals and businesses through some of the most complex and high-stakes tax matters imaginable.

A proud San Diego native and three-time graduate of the University of San Diego, Mr. Shamoun’s journey into tax law was shaped early by his academic foundation in accountancy and law. He earned his Bachelor of Arts in Accountancy, followed by his Juris Doctor and an LL.M. in Taxation, credentials that laid the groundwork for a career defined by precision, strategy, and an unwavering commitment to client outcomes.

As the founder and CEO of RJS LAW, Mr. Shamoun leads a team of experienced tax attorneys who focus exclusively on federal and state tax matters. The firm’s practice spans civil tax controversy, criminal tax defense, international tax, estate planning, and complex business matters. From mom-and-pop business owners to multinational companies, Mr. Shamoun’s client-centered approach ensures every case receives meticulous attention and a tailored legal strategy.

Over the course of his career, Mr. Shamoun has represented clients before the Internal Revenue Service (IRS), Franchise Tax Board (FTB), Employment Development Department (EDD), and California Department of Tax and Fee Administration (CDTFA). His work has resulted in hundreds of millions of dollars saved in penalties, assessments, and tax liabilities. In criminal tax matters, where the stakes include potential incarceration, his results are especially notable. Leveraging his sterling reputation with the U.S. Attorney’s Office and District Attorneys across California, Mr. Shamoun has successfully negotiated reduced charges for clients and, in many cases, helped them avoid criminal prosecution altogether.

One of the most striking examples of his leadership came during the aftermath of pandemic relief programs. Mr. Shamoun and his team managed some of the nation’s most complex Paycheck Protection Program (PPP), Economic Injury Disaster Loan (EIDL), and Restaurant Revitalization Fund (RRF) cases. In one notable case, RJS LAW represented a client under active IRS criminal investigation for alleged misuse of PPP and EIDL funds. Despite the IRS and Department of Justice’s near-perfect conviction rate, Mr. Shamoun and his team negotiated a resolution that avoided criminal indictment entirely, a result that speaks to both legal skill and strategic credibility.

Beyond his practice, Mr. Shamoun is deeply committed to education and mentorship. He serves as an adjunct professor at the University of San Diego School of Law and School of Business, teaching courses such as Tax Practice and Penalties and Federal Tax Procedures and Policies. He also sits on the Boards of Visitors and Advisors for USD’s law and business schools. In 2016, he co-founded the nationally acclaimed USD School of Law – RJS LAW Tax Institute, which annually brings together top tax professionals from across the country while raising scholarship funds for students.

Recognition has followed naturally. RJS LAW has been named San Diego’s Best Tax Law Firm by the San Diego Union-Tribune Readers Poll for seven years, and Mr. Shamoun himself has received numerous honors, including USD Law’s Distinguished Alumni Award, AV Preeminent status from Martindale-Hubbell, San Diego Super Lawyers recognition, and CEO of the Year honors from the San Diego Business Journal.

San Diego Community Advocate

In addition to his professional success, Mr. Shamoun remains deeply connected to the San Diego community. He is an active supporter of local organizations and causes, a business and real estate investor, and the owner of Café Bella in Ocean Beach, which was named San Diego’s Best Coffee Shop by the Union-Tribune. Through both his personal efforts and the initiatives of RJS LAW, Mr. Shamoun and his team are devoted to charitable giving, philanthropy, and volunteer work that strengthen the fabric of San Diego and beyond. RJS LAW regularly evaluates and supports nonprofit missions, donating billboard space and resources to organizations such as The Salvation Army, Girl Scouts of San Diego, Susan G. Komen, Noah Homes, Walden Family Services, and other community partners to raise awareness and impact. The firm also champions diversity, education, and civic engagement, helping local charities, schools, and businesses thrive while encouraging collaborative growth throughout the region.

Above all, Mr. Shamoun is a devoted father who values family and community just as much as professional excellence. His story is one of relentless advocacy, thoughtful leadership, and meaningful impact. Through RJS LAW, he continues to set the standard for tax representation in San Diego and beyond, proving that exceptional legal skill, when paired with integrity, compassion, and purpose, can truly change lives.