When regs lose their deference: Three cases rewrite the tax playbook

Doug McHoney (PwC’s International Tax Services Global Leader) is joined by Laura Williams, an international tax partner in PwC’s Washington National Tax Services office and former branch chief in the IRS Office of Chief Counsel. Doug and Laura discuss the role of Treasury regulations, Section 7805(a), and the post-Loper Bright limits on agency deference and delegated authority. They explain why TCJA’s mismatched effective dates created a ‘donut hole’ and examine three recent regulation-validi...