But defendant provides no persuasive reason why attorneys should enjoy a special exemption from a tax that applies uniformly to all persons doing business within the City of Portland. Attorneys may be acting as officers of the court when they earn revenue, but any effect on the judicial branch that results from a general tax on their income is far too tangential to rise to the level of a separation of powers issue. That definition can rationally be applied to defendant's activities with the City of Portland even if his principal place of business is elsewhere. Amicus 's argument appears to reflect older notions that a municipality or state is limited to taxing a person's principal place of business. Oregon, however, has not adopted that limited view of a municipality's taxing authority.
Defendant advances a second argument.
He argues that Portland's business license fee violates Article IX, section 1a, of the Oregon Constitution, because it is a poll or head tax. A poll or head tax is a fixed tax assessed on each eligible person. Article IX, section 1a, which prohibits those taxes, was added to the constitution in 1910. The problem that the measure's supporters perceived was that poll or head taxes are not graduated. Id. Portland's business license fee is not a head or poll tax.