Phil has been working in state and local tax since 1994. He assists clients with all aspects of state and local tax compliance, focusing on tax controversy matters. With past experience working for a state agency, Phil can provide his clients with valuable insight in audit defense and protests.

Phil spent a combined 20 years working for the Colorado Department of Revenue, where he designed and implemented one of the nation’s first state tax voluntary disclosure programs. His career at the Colorado Department of Revenue also included managing the field audit policy function and serving as director of the Office of Tax Policy Analysis, which involved centralizing the department’s policy functions. Phil’s past experience also includes working in the state and local tax practice of a Big Four firm and serving as Colorado’s representative on the Multistate Tax Commission.

Selected Speaking Engagements

  • Long-Term Implications of Wayfair for State Income Taxes: Retroactivity, Nexus, Apportionment, and Impact on P.L. 86-272
    (Federal Bar Association Annual Tax Law Conference, March 2019)


  • BA, economics and English literature, University of Colorado
  • JD, law, University of Texas at Austin
  • LLM, public international law, University of London

Insights from Phil Horwitz