I’m a big believer in the Laffer Curve, which is the common-sense proposition that changes in tax rates don’t automatically mean proportional changes in tax revenue. This is because you also have to think about what happens to taxable income, which can move up or down in response to changes in tax policy.
The key thing to understand is that incentives matter. If you raise tax rates and therefore increase the cost the engaging in productive behavior, people will be less likely to work, save, invest, and be entrepreneurial. And they’ll figure out ways to engage in tax avoidance and tax evasion to protect the interests of their families. In other words, taxable income will be lower because of higher tax rates.
Likewise, people will be more willing to earn – and report – taxable income if tax rates are reduced.
If you don’t believe me, look at this incredible data showing how the rich paid for more money after Reagan slashed their tax rates.
This doesn’t mean that “tax cuts pay for themselves.” That may happen in rare circumstances, but the real issue is the degree of “revenue feedback.”
For some types of tax changes, such as lowering tax rates on the “rich,” the revenue feedback may be very large because they have considerable control over the timing, level, and composition of their income.
In other cases, such as providing a child tax credit, the feedback may be very small because there’s not much of an impact on incentives to engage in productive behavior.
This doesn’t necessarily mean one type of tax cut is good and the other bad. It just means that some changes in tax policy produce revenue feedback and others don’t.
Even leftists recognize there is a Laffer Curve. They may argue that the “revenue-maximizing rate” is very high, with some claiming the government can impose tax rates of more than 70 percent and still collect additional revenue. But they all recognize that there’s a point where revenue-feedback effects are so strong that higher rates will lose revenue.