Realtors and home builders strongly defend the mortgage interest deduction as a way of increasing homeownership, which is supposed to be a good thing. But does it really work that well?
Edward Glaeser doesn’t think so. While he agrees that there are social benefits to increasing homeownership, he notes that the mortgage-interest deduction mainly benefits the wealthy, who are almost always homeowners anyway. He also finds that, while the subsidy has changed significantly over the years, those changes have not been reflected by changes in homeownership.
Charging taxes on interest is double taxation because the people who earn the interest also have to pay taxes on it. So, as Wikipedia notes, when Congress created the income tax in 1913, it allowed people to deduct the interest from all personal loans, not just mortgages. But in 1986, Congress (no longer worried about double taxation) repealed that deduction for all loans other than home loans. The stated reason for leaving that deduction was to promote homeownership.
