From the New York Times, of all places, comes an article about how regulation contributes to income inequality:
...the escalation of land-use controls that drive up rents in desirable metropolitan areas; favoritism toward market incumbents via state occupational licensing regulations (for example, associations representing lawyers, doctors and dentists that block efforts allowing paraprofessionals to provide routine services at a lower price without their supervision).
These are just some of the causes contributing to the 1 percent's high and rising income share. Reforming relevant laws can make markets more efficient and egalitarian