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 Co. v. C.I.R., 227 F.2d 16, 19-20 (3rd Cir. 1960).) All other taxes are typically called "indirect taxes," within their tax an event, rather than an individual or property by itself. (Steward Machine Co. v. Davis, 301 U.S. 548, 581-582 (1937).) What was basically a straightforward limitation on the power of the legislature bas...