Michael Hilkin represents clients in all aspects of complex state and local tax matters. He has a particular focus on tax controversy and transactional issues relating to state and local income, franchise, sales and use, gross receipts, and other business taxes. Michael has extensive experience handling state and local tax issues before US administrative and judicial systems, including arguing cases before state courts and state supreme courts. He also regularly advises clients on personal income tax issues, especially those concerning residency.

Michael frequently speaks on state and local tax issues before the Council on State Taxation, Tax Executives Institute, the New York University Institute on State Taxation, the Paul J. Hartman SALT Forum, and the Institute for Professionals in Taxation.

Brian H. Jenn focuses his practice on US and international tax matters for US and foreign multinationals and other clients. As former Deputy International Tax Counsel (DITC) for the US Department of Treasury, Brian has extensive experience and insight on the Tax Cuts and Jobs Act (TCJA), having been deeply involved in the process of issuing proposed and final regulations and other guidance implementing the TCJA. Brian also has significant insights on taxation of the digital economy, transfer pricing and US taxation of foreign currencies.

Prior to joining McDermott, Brian spent several years at the US Department of Treasury where he was an attorney advisor, and most recently DITC. While at Treasury, he served as co-chair of the Organisation for Economic Co-operation and Development’s (OECD) Task Force on Digital Economy and as US delegate to the Committee on Fiscal Affairs. In this capacity, Brian led Treasury’s engagement at the OECD on digital tax issues, playing a central role in discussing tax challenges associated with the digitalization of the economy, as well as the development of new international norms for allocating tax rights among countries.

Brian also advises clients with international operations on transfer pricing issues, such as supply chain structuring and intellectual property planning. As US delegate to the OECD’s Working Party 6 throughout the G20-OECD Base Erosion and Profit Shifting (BEPS) project, Brian negotiated major changes to international transfer pricing standards, including changes to the OECD Transfer Pricing Guidelines chapters on intangibles, cost contributions arrangements, risk and recharacterization, and low-value added services.

In addition, Brian was one of the primary drafters of a recently issued detailed set of regulations governing US taxation of transactions involving foreign currencies.

Before joining the Treasury, Brian spent several years in private practice, where he advised clients in various sectors, including technology, pharmaceutical, financial services and consumer products. He handled aspects of international tax planning including foreign tax credits, foreign currency issues, Subpart F, intangible property transfers, transfer pricing and treaty interpretation.

Prior to law school, Brian served as a staff economist to the White House Council of Economic Advisors where he assisted the chairman and members of the council in advising the president on tax policy and other public finance issues. In addition, he served as senior economist to the Joint Economic Committee of Congress where he advised the chair regarding tax policy, including issues related to the economic implications of potential international tax reforms.

Shawn O’Brien is nationally recognized by his peers and clients as a leading tax practitioner with a focus on tax litigation and controversies involving state, federal and international tax authorities. Drawing on his 25 years of experience, Shawn represents clients in tax examinations and administrative appeals and, when necessary, serves as a forceful advocate in litigation before the US Tax Court, US district courts, the US Court of Federal Claims, state courts and federal appellate courts. Shawn is the managing partner for the firm’s Houston office.

Clients interviewed in the Chambers USA Legal Guide 2024 shared that Shawn is “a trusted adviser and his level of service is superb” and he “has been a good strategic tax partner for our company,” particularly noting his “in-depth knowledge of our industry.”

Shawn’s experience spans a broad range of tax issues that affect many different industries, including energy, renewables, financial services, life sciences, manufacturing, media and entertainment, technology and aviation. He advises domestic, foreign and multinational corporations, partnerships, master limited partnerships, real estate investment trusts and limited liability companies on tax issues in connection with foreign and domestic transactions.

He also counsels clients in disputes involving transfer pricing, debt versus equity, loss carrybacks, international withholdings, advance pricing agreements, tax shelter disallowances, research and development tax credits, changes in accounting methods, captive insurance, related-party transactions, repatriation structures, inbound distributors, foreign credit transactions and penalty abatements. Shawn has also developed a market-leading federal and state excise tax practice that advises some of the largest corporations on excise tax planning and controversies.

Sarah G. Raaii devotes her practice to issues impacting group health and welfare benefit plans by counseling employers, digital health and point solution clients, plan administrators, insurers, consultants and other health plan service providers.

Sarah advises her clients on healthcare reform issues; consumer-driven health benefits; self-funded and fully insured health plans; data privacy and the Health Insurance Portability and Accountability Act (HIPAA); wellness programs; cafeteria plans; and regulatory, sub-regulatory and legal compliance. She provides guidance on the Affordable Care Act (ACA); the Employee Retirement Income Security Act (ERISA); health plan transparency; mental health parity; the No Surprises Act; the Consolidated Omnibus Budget Reconciliation Act (COBRA); flexible benefit plans; health reimbursement accounts (HRAs); health savings accounts (HSAs); plan network design; multiple employer welfare arrangements (MEWAs); association health plans; captive insurance arrangements; and other health benefits issues.

Sarah drafts and negotiates complex agreements between employers, health plans, third-party administrators, pharmacy benefit managers, carriers, consultants and other health plan service providers. She also counsels digital health, telehealth and point solution entities; third-party administrators; pharmacy benefit managers; and other benefit administrators on partnering with employers, group health plans and insurers. As co-chair of the Firm’s Post-Roe Working Group – a multidisciplinary team of lawyers providing clients with reproductive health guidance – Sarah has advised hundreds of health plans and benefit administrators on health benefits following the end of Roe v. Wade.

Additionally, Sarah routinely analyzes frequently changing health benefits laws and regulations and recommends risk mitigation strategies. She provides strategic due diligence and health benefits design, implementation and transition advice on issues arising from corporate and private equity mergers, acquisitions and other transactions.

Sarah frequently publishes and presents on health benefits trends and developments and has been quoted on health plan issues in prominent media outlets, including The New York Times, The Wall Street Journal, Bloomberg Law and Law360.

Prior to joining the firm, Sarah worked at the White House for the National Economic Council, where she implemented the ACA with leaders from the Executive Office of the President, the US Department of Labor, the US Department of Health and Human Services, and the US Department of the Treasury. She previously collaborated with in-house lawyers and federal and state government relations professionals in the leadership development program of a Fortune 500 global insurance and financial services corporation.