Transparency and simplicity
Another concern is that the complicated tax codes of developed economies offer perverse economic incentives. The more details of tax policy there are, the more opportunities for legal tax avoidance and illegal tax evasion; these not only result in lost revenue, but involve additional deadweight costs: for instance, payments made for tax advice are essentially deadweight costs because they add no wealth to the economy. Perverse incentives also occur because of non-taxable 'hidden' transactions; for instance, a sale from one company to another might be liable for sales tax, but if the same goods were shipped from one branch of a corporation to another, no tax would be payable.
To address these issues, economists often suggest simple and transparent tax structures which avoid providing loopholes. Sales tax, for instance, can be replaced with a value added tax which disregards intermediate transactions.