Flat-tax adequacy fails because rich consume more public services

Evidence

That leaves our overall tax rate, which I believe should be completely progressive: Rates rise as income rises. All wage income that is over the living allowance deduction would be taxed at the progressive rate, and investment income, inheritances, and property sales would be taxed the same way—no more preferential treatment. I used to believe that vertical equity, based on ability to pay, could include a flat-rate system, where everyone pays the same percentage rate in taxes regardless of income, because those with greater incomes would still pay more in taxes. But I’ve come to value the symbolism of a progressive tax system that does more than just require higher-income Americans to pay more taxes (which could happen with a flat tax); they need to pay taxes at a higher rate. As I once explained to my tax class, rich people take up an inordinate amount of services. For example, the entire judicial system benefits them when contracts they enter into are upheld. — Dorothy A. Brown, The Whiteness of Wealth, 525

Categorization

• QUESTION: Is there solid empirical work on how much more public-service value wealthy households consume, or is this only an intuition?