The Pennsylvania Constitution requires that, “All taxes shall be uniform, upon the same class of subjects, within the territorial limits of the authority levying the tax and shall be levied and collected under general laws,” which is known as the uniformity clause. In 2017, the city of Philadelphia reassessed commercial and industrial properties for the 2018 tax year due to pressure from Philadelphia City Council. The city proclaimed that it had better information to assess the value of such commercial and industrial properties, and for that reason, the city’s reassessing only those specific classes of property did not violate the uniformity clause. The city did not focus on residential properties as part of the reassessment because the city determined that the residential properties were already assessed at or near fair market value. In 2017, a group of commercial property owners sued the city asserting that the city’s selective reassessment scheme violated the uniformity clause of the Pennsylvania Constitution. In Duffield v. City of Philadelphia, No. 1536 (Phil. Cty. Comm. Pl. 2017), the Philadelphia Court of Common Pleas found that the city violated the uniformity clause by reassessing commercial real estate and not residential properties. Judge David Cohen concluded that real estate in a single jurisdiction must be treated as a single class for uniform treatment, and taxing authorities are not permitted to treat one sub-classification of properties differently from another. The city appealed the decision and final disposition is still pending. However, Duffield is just the most recent case in a line of many that shape the ever-changing Pennsylvania tax assessment laws and procedures.

The Pennsylvania tax assessment process is unlike any other in the United States. Pennsylvania does not have a state agency to oversee the property valuation and assessment process, or to supervise and ensure uniformity in the assessment process from county to county. Instead, each county in Pennsylvania has a designated chief assessor responsible for supervising the assessment office that determines assessed values for local real estate taxation. Additionally, Pennsylvania is one of only six states that does not have statutorily mandated reassessments on a fixed cycle. For example, Beaver County’s last reassessment occurred in 1982, compared with Allegheny County’s last reassessment of 2012 effective for 2013 Beaver County Judge Dale Fouse has ordered Beaver County’s assessment office to reassess Beaver County’s roughly 96,000 parcels by 2023 due to the county’s use of 1982 for its base year. The countywide reassessment year is significant in Pennsylvania because that year becomes what is known as the “base year” for each county under the Pennsylvania assessment and valuation system. A base year is defined as“the year upon which real property market values are based for the most recent countywide revision of assessment of real property or other prior year upon which the market value of all real property of the county is based. Real property market values shall be equalized within the county and any changes by the board of assessment appeals shall be expressed in terms of such base year values.” Under a base-year system of valuation, a county performs a countywide reassessment of all real property in the base year, and then uses each property’s base-year assessment as that property’s basis for taxation in the base year, as well as its basis (i.e., assessed value) in subsequent years, see Downingtown Area School District v. Chester County Board of Assessment Appeals, 590 Pa. 459 (2006).