Studies by Metcalf
et al. (2008) and Metcalf (2009) consider the possible distributional impacts of carbon taxes in the United States.
[202] The 2008 study considers three recent tax bills introduced to the
US Congress. The taxes themselves are highly
regressive, but when revenues from the tax are returned lump-sum, the taxes become
progressive. The 2009 study looks at a carbon tax combined with a reduction in
payroll taxes. It is found that this combination can be distributionally neutral. With an adjustment in
Social Security payments for the lowest-income households, the carbon tax policy can be made progressive.