Winston & Strawn is expanding its Washington office with the addition of James Mastracchio and Susan Seabrook as partners in its global tax controversy practice.
The pair arrived from Eversheds Sutherland, where Mastracchio was head of the firm’s federal tax controversy and criminal tax practices. He will co-lead Winston & Strawn federal tax controversy and criminal tax matters practices in Washington.
Seabrook, who will be the other co-lead, had worked prior to private practice as a special assistant U.S. attorney and a senior trial attorney with the IRS Office of Chief Counsel. She also worked at the National Office Industry Counsel for the life insurance industry.
“Jim and Susan bring exceptional value to our D.C. litigation team,” said David Rogers, managing partner of Winston & Strawn’s Washington office, in a statement. “They are recognized for their unique experience managing cross-border and multi-jurisdictional tax issues.”
Mastracchio has worked with public and private companies, boards of directors and senior executives facing civil and criminal tax investigations and prosecutions on allegations of tax violations.
He said the tax controversy practice has changed significantly in recent years.
It “not only requires a thorough knowledge of domestic tax enforcement and tax litigation,” he said, “but increasingly, clients require assistance with treaty interpretation and information exchange agreements, and advice on how best to coordinate with competent authorities in the U.S. and abroad.”
He has appeared before regulatory bodies and tax authorities in various countries and advises on the interpretation of intergovernmental agreements and treaty protocols in connection with tax investigations, he told Bloomberg Law.
Seabrook, whose clients have included those in the insurance and re-insurance industries, energy and IT/government contracting sectors, noted that client “legal challenges are complex and often sensitive and require an administrative result-oriented resolution.”
Tom Fitzgerald, Winston & Strawn’s chairman, said in a statement that “given the trend our clients are facing as a result of increased coordination across governmental agencies, we are excited to have Jim and Susan bolster our various regulatory and litigation defense teams.”