The tax code is often used to achieve economic, political and social aspirations even if the primary purpose of the law is to provide the federal government with revenue. For example, the tax law gives a deduction for mortgage profit cost on debt acquired by primary dwellings to promote home ownership. Furthermore, the tax law does not permit renters a deduction for rent fees compensated to counterbalance the benefit of non-recognition of ruling out of accredited owner occupied rent fee. An income tax system would charge a tax on the accredited rent fee for owners who live in their own residences and would not permit deduction on mortgage interest, if that system does not favor both renting and owning residences.

Because of the reality that the tax code is being used by the government for social policy, the tax code all together seems to be short of a consistent organizing principle. This shortage has questionably become exaggerated over time, as a result of the relationship between consecutive modifications of the law and the feedback of the private sector to those modifications. This goes on in an unending cycle, which results in the code’s complexity.