Rent Control Feeds Inequality in San Francisco

San Francisco is famously America's most expensive city. That means there's all kinds of political agitation for rent regulations and other affordable housing mandates. But a new study from the National Bureau of Economic Research finds that the city's rent control laws help a certain set of haves while costing a larger set of have-nots.

In 1994, the City by the Bay imposed rent regulations via ballot initiative on "small multifamily housing built prior to 1980." This allowed Stanford researchers to compare units constructed before and after that year. As...