HARRISBURG -- Allegheny County has been added to a list a counties where "spot appeals'' of property assessments would be forbidden if new legislation is enacted.

Rep. Marc Gergely, D-White Oak, has joined a renewed effort by Rep. Tim Seip, D-Schuylkill, to stop school boards from initiating spot appeals on residences and businesses after they are sold -- usually at a higher price than they had before -- which means the new owner's taxes rise, sometimes dramatically.

The legislators said spot appeals are bad because they cause the new homebuyer to pay much higher property taxes than his neighbors, whose homes often have lower assessments because they were bought years before.

Mr. Gergely complained that the McKeesport School District had planned to do spot appeals on as many as 500 homes and 74 businesses, before he complained and the idea was shelved.

Second-class counties, meaning Allegheny, hadn't been included in Mr. Seip's bill, which covers third- through eighth-class counties. The only other county now not included in the proposed spot appeals ban is Philadelphia, the state's largest county. It has just undergone a major reassessment.

Some taxing bodies, such as school boards or municipalities, decide to challenge assessments of recently sold properties because a higher price means more tax revenue. Last year, Gov. Ed Rendell vetoed a bill banning spot appeals because, in the absence of regular property reassessments, school boards don't have any other way of getting more revenue.

Mr. Seip's bill "would essentially eliminate the right of school districts and municipalities to challenge assessments when a property is dramatically underassessed,'' Rendell aide Chuck Ardo said.

Few counties do annual or regular reassessments of properties, sometimes letting it go for years, because commissioners fear an angry reaction by property owners over the higher values.

Some officials think the Legislature should require counties to do reassessments on an annual or regular schedule, so property values stay relatively up to date, but that move has proven controversial also.