Washington State Tax Conference 2026 WEBCAST

Aaron Johnson, Shareholder, Tax Attorney & Professor, Ballard Spahr

Aaron is a partner at Ballard Spahr Lane Powell in Seattle, WA, where he co-leads the firm’s SALT team and represents multinational, U.S., and regional businesses in SALT matters including tax litigation, audit defense, appeals, planning and structuring tax efficient transactions. Previously, he was an experienced tax manager at PwC where he managed a multistate practice and tax controversies, a judicial law clerk, stockbroker and financial advisor, and an enlisted U.S. Army Soldier. He is the WA Bar SALT Committee Chair, a member of the Legislative and founder of the Tax DEI committee; on the ABA SALT Executive Committee; and teaches tax at UW School of Law. He previously taught corp. tax at UW Foster and fed. tax at SPU (20-21 prof. of the year). Aaron is an appointed member of the WA DOR’s Business Advisory Council and an advisory member to the Assoc. of WA Bus. (AWB).

Brett Durbin, Ballard Spahr

Brett S. Durbin counsels clients on SALT issues spanning both transactional and litigation matters, including general business planning and representing clients before state tax agencies, the Washington State Board of Tax Appeals, and all levels of courts across the state. Brett’s experience includes serving as the Assistant Attorney General for the Washington State Attorney General’s Office, where he represented the Washington State DOR. He is the Washington State Bar Association (WSBA) Tax Section’s Legislative Chair and past Section Chair, and he is on the ABA Tax Section SALT Executive Committee, where he is the Co-Chair of both the Model Tax Tribunal Taskforce and the Website Committee. For tax litigation and controversy, he was voted as the 2023 “Seattle Lawyer of the Year,” is listed as one of The Best Lawyers in America®, and has been awarded the Excellence Award from the Institute for Professionals in Taxation. He received his B.A. from Western Washington University and his J.D. from the University of Washington.

Darcy Kooiker, Managing Director, EY (Seattle)

Darcy is a CPA licensed in Washington state and has focused in the area of state and local taxation since 1991. She started her career in the government sector working for the City of Bellevue’s tax department as an intern then became a Revenue Auditor for the State of Washington Department of Revenue. Darcy has since been a tax consultant working at several accounting/consulting firms in the Seattle area. In this capacity Darcy helps clients with nexus issues, tax minimization reporting and restructuring opportunities, transaction planning, audit management and administrative appeal representation. Darcy’s specialty is Washington tax and she enjoys helping businesses understand how the complex state and local sales/use taxes and Business and Occupation tax complex apply to their activities. Business organizations seek her technical expertise for speaking engagements and articles including Bloomberg, Institute for Professionals in Taxation, Journal of State Taxation, the Washington and Oregon Society of CPAs, and many others. She has served as an advisor to the Washington Department of Revenue and the Association of General Contractors of Washington. Darcy is an active member of the Association of Washington Business and Washington Society of CPAs. She has testified before the Washington State legislature on tax matters and has influenced tax legislation. She received her accounting degree from the University of Washington’s Seattle campus, and a Masters Certificate in State and Local Taxation from the University of Wisconsin. She has also been an adjunct professor at Gonzaga University teaching a State Tax Concepts class in the Masters Accounting program. She is the co-chair of the Institute for Professionals Seattle Luncheon Group and is also an Avalara Certified Implementation Partner.

Elizabeth Arnold, Tax Senior Manager, Vine Dahlen PLLC

Liz Arnold is a CPA and a people person who thrives on connecting with clients to better understand their needs and aspirations. Through these connections, she ensures her clients’ tax strategies—whether for individuals, families, or partnerships—align with their long-term goals and values. Specializing in estate, gift, and income tax strategies, Liz helps clients navigate complex estate structures, minimize tax liabilities, and incorporate charitable giving into their financial plans.

A Pacific Northwest native and proud CWU graduate, Liz loves spending time outdoors with her husband and daughter. Whether it’s camping, exploring new places, or enjoying a weekend getaway, she’s always up for an adventure.

Lindsay Chuang, Partner - Private Tax, EY (Seattle)

Lindsay Chuang is a partner at Ernst & Young LLP. Chuang has been a member of the EY Private Client Services Tax practice for over a decade. She specializes in assisting entrepreneurs and business founders, high-net-worth individuals, and private and family businesses with their individual and business-related tax issues. Chuang graduated from the University of British Columbia with a Bachelor of Commerce in Accounting. She is a certified public accountant (CPA) licensed to practice in Washington, Vermont and California, and is a member of the American Institute of Certified Public Accountants (AICPA).

Mark Hawkins, Director, Baker Tilly (MA Seattle)

Mark Hawkins is a director in Moss Adams’ State and Local Tax Practice. He has consulted in state and local tax matters since 2001. Mark provides tax advisory services to clients in a wide array of industries including retailing, manufacturing, professional services, transportation, and agriculture. Mark assists clients in analyzing the state tax implications of business reorganizations and other transactions. Mark also assists clients in their state and local tax compliance functions. Including apportionment and gain sourcing, as well as during audits and examinations and represents them in administrative proceedings with state departments of revenue and taxation. More recently, Mark consults with clients on pass-through entity elective taxes and their potential for federal income tax benefits to their owners. Mark holds a BA in history and political science from the University of Washington and a JD from Ohio State University.

Megan Chyan, Senior Consultant, EY (Seattle)

Megan started her career in the government sector as an internal auditor for Pierce County Budget and Finance and also worked for the City of Tacoma Finance Department. In 2017, she became a Revenue Auditor for the State of Washington’s Department of Revenue and has specialized in Washington state and local taxes ever since. During her time with the Department, Megan contributed to the development of audit practices in emerging industries and helped establish tax registration procedures with Washington’s tax statutes through the State’s Voluntary Disclosure program. Megan is now a senior consultant at Ernst & Young in Seattle, helping clients with state tax compliance problems such as determining if nexus applies, tax registration and reporting, audit management and administrative appeal petitions. Her focus is in helping businesses understand how Washington’s Business and Occupation tax system and the complex state and local sales/use taxes apply to their operating activities.

Rachel Roberson, Senior Manager, Sweeney Conrad

Rachel Roberson, CPA, is a Director of SALT at Sweeney Conrad PS. Rachel assists clients in a broad range of industries with consulting and planning related to Washington and city taxes and audits. She also consults on multi-state nexus, sales and use taxes, and risk analysis and remediation. She is passionate about advising clients to understand more than just what the tax rules say today. She enjoys analyzing tax legislation before it is passed and working within industry groups to make it easier for businesses to comply and understand

Sonjia Barker, Shareholder, State and Local Tax, Perkins & Co PC

Adept at simplifying daunting tax situations, Sonjia draws on her Big 4 accounting firm and Washington Department of Revenue experiences to deliver actionable solutions to clients. With her impressive dossier and huge heart for helping others, she’s a powerhouse on any tax team and the leader of our SALT practice.

A military kid, Sonjia grew up in Illinois and California but now calls the beautiful Kitsap Peninsula in Washington state her home. Poised between Seattle and the Olympic National Forest, the area is the perfect playground for Sonjia’s outdoorsy family. An avid camper, Sonjia is on a quest to visit all the country’s national parks, though none may top her favorite—the Badlands.

When she’s not sleeping under the stars, you might find Sonjia enjoying a metal concert with thousands of her best friends. She’s been a huge Metallica fan since she was 12 and is surprised as anybody that she hasn’t outgrown her punk rock phase.