An Examination of the Relations among Tax Preferences, Implicit Taxes, and Market Power in a Noncompetitive Market
We examine whether market power within a noncompetitive industry is related to a firm's ability to retain the benefits received from statutory tax preferences. Using both a market-based measure and an accounting-based measure proposed by Dunbar and Sansing (2002), we estimate tax preferences for a sample of 60 defense contractors for the three years preceding (1984–1986) and immediately following (1988–1990) the passage of the Tax Reform Act of 1986 (TRA86). We confirm that defense contractors enjoyed positive tax preferences in 1984–1986, which decreased significantly with the passage of TRA86. We find a negative and significant relation between changes in tax preferences and changes in pre-tax returns, which is consistent with implicit tax theory and supported by prior empirical work. We also find that this relation is significantly less negative for firms ranked among the Top 100 defense contractors than for unranked contractors. We conclude that market power is positively related to a firm's ability to retain the benefits of tax preferences, where market power is defined as relative position within the noncompetitive defense contracting market.