Homes in poor neighborhoods are taxed at roughly twice the rate of those in rich areas

The Washington Post calls our attention to a study, "Reassessing the Property Tax," by Christopher Berry of the University of Chicago.  From the abstract:

Using data from millions of residential real estate transactions, this paper shows that assessments are typically regressive, with low-priced properties being assessed at a higher value, relative to their actual sale price, than are high-priced properties. Within a jurisdiction, homes in the bottom decile of sale price face an assessment level, as a proportion of price, that is twice as high as that faced by homes in the top decile, on average. As a result, the property tax disproportionately burdens owners of less valuable homes. Such regressivity is evident throughout the US. This result cannot be explained by measurement error in sale prices, or by explicit policy choices, such as assessment limits. Rather, regressivity appears to result from limitations in the data and methods used in assessment.

The author believes this isn't deliberate, but that probably isn't fully true.  There are policy decisions that impact relative assessments, at least in some cities.

For example, New York City has a residential property tax assessment methodology that pools condominiums and cooperative apartments with multiunit rental buildings, thereby undervaluing owner occupied properties, while traditional single family housing and small apartment buildings are valued in line with current property value ("Make New York City Property Taxes Fair," Regional Plan Association).

Wealthy property owners and real estate interests don't want to change the system ("De Blasio Delay Plus Pandemic Means Property Tax Reform Appears Off the Table This Year," Gotham Gazette).

In other cities like Philadelphia and Baltimore, new and converted housing is taxed at a much lower rate, usually for the first ten years of ownership, creating a similar dynamic to that of New York City, where higher income residents pay lower taxes compared to legacy residents.