There are several justifications for the corporate tax, including the claim that the corporate tax enhances progressivity in the tax code. This claim is based on two assumptions. One, that corporate tax incidence is primarily borne by capital (as opposed to labor); and two, that capital is concentrated among wealthier taxpayers. Since economists commonly disagree on the incidence of the corporate tax, there can be little agreement about whether the corporate tax is in fact progressive; corporate tax progressivity remains an open question.