As Philadelphia’s Office of Property Assessment faces ongoing criticism from homeowners and lawmakers over residential reassessments, its chief assessment officer has resigned, city officials announced Friday.

Mike Piper, whose fate had been sealed when City Council signaled last year it would not support his reappointment to another term, “has decided to pursue another opportunity,” Finance Director Rob Dubow said, without elaborating.

In an email late Friday, Piper said he is taking a job with the city assessment office in Chicago.

A national search for Piper’s replacement had already been underway. Until that is complete, Deputy Chief Assessor James “AJ” Aros Jr. will serve as interim chief assessor, Dubow said.

Piper was a career employee who had led OPA since 2014. But the office, which sets property values that ultimately shape the annual tax bills for hundreds of thousands of residents and businesses, had drawn increasing scrutiny and criticism.

The city announced last month that it would leave property values largely unchanged next year, following two years of revaluations that resulted in increased taxes for many homeowners.

City Council pressed OPA over those reassessments, and in July a judge ruled that the city and School District must repay nearly $50 million in tax revenue because it unconstitutionally targeted commercial properties in a 2018 revaluation. Piper was one of several city officials to testify at the trial.

The Kenney administration has defended its assessments and Piper’s work. He worked in various roles in Philadelphia’s property assessment offices for 28 years; as chief assessor he was paid an annual salary of $157,185.

"As chief assessment officer, Mike devoted countless hours — including evenings and weekends — hearing and addressing the concerns of residents about their assessments, concerns voiced at by email, phone calls, visits by residents to his office, and community meetings,” Dubow said. “Mike oversaw the professionalization of property assessment in Philadelphia, instituting training for existing staff and setting higher standards for the hiring of new staff.”

The change in the Philadelphia’s office leadership comes as the city prepares to launch a long-awaited software program known as Computer Assisted Mass Assessment (CAMA) that will assist internally with property assessments.

Aros has been working in property assessments in Philadelphia since 2004.

“Most recently, AJ has been involved in the implementation of the new CAMA assessment system, which is to be launched this spring, and he regularly represents the department at meetings with other city agencies, City Council, and community groups,” Dubow said.