Councilman David Oh introduced a resolution Thursday giving Council the authority to subpoena the Office of Property Assessment for more detailed information about the recent citywide reassessment that was key to Mayor Nutter's property tax reform, the Actual Value Initiative (AVI).

The office (OPA) on Friday released a 15-page document on its website that included an explainer of how properties were assessed, as well as "the formula." Council members, some hearing from angry homeowners confused by AVI, had been clamoring for weeks to see "the formula" for assessing properties.

"We have asked many times in many different ways to get the data set that was used so we can see exactly how the assessments were done and we can verify that they're accurate and done properly," Oh said.

In a Council hearing last month, Chief Assessor Richie McKeithen warned that mass appraisals involved higher mathematics, and the formula would do little for the layman's understanding of the process.

(One could hardly argue with that, considering the formula listed in the 15-page explainer is Market Value = Constant * B1^X1 * X2^LN(B2).....* BX 1^XX-1 * XX^LN(BX).)

Oh complained that the explainer would not allow anyone to duplicate OPA's work reassessing an individual property – he said he wants enough information to able to do that.

He also said he wants to see the 20,000 property sales that were deemed to be good indicators of the market and were used as barometers of the reassessment's accuracy. McKeithen said the reassessment came comfortably within industry standards for accuracy.

Oh said citizens' group, specifically The Crosstown Coalition, "have asked us to make sure we get this data."

The coalition, a collection of neighborhood groups mostly representing areas of the city facing tax hikes under AVI, are working on a report on the reassessment. The coalition has complained about not having access to OPA data, but nonetheless said a preliminary analysis found the reassessment to be "not even close" to industry standards.

Oh said he thought the administration was "stonewalling."

"For some reason they don't want to provide the information that will allow both citizens … and the Council to follow exactly what they did to verify their results," he said.

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