The courts have generally held that direct taxes are restricted to taxes on people (variously called capitation, poll tax or head tax) and property. (Penn Mutual Indemnity Denver. v. C.I.R., 227 F.2d 16, 19-20 (3rd Cir. 1960).) All the taxes are known as "indirect taxes," as these tax an event, rather than human being or property by itself. (Steward Machine Co. v. Davis, 301 U.S. 548, 581-582 (1937).) What seemed to be a straightforward limitation on the power of the legislature based on the top...