As many as 60 of the 67 counties in Pennsylvania are vulnerable to a legal challenge to their property assessment systems as a result of the Supreme Court decision that overturned Allegheny County's assessment system Wednesday.

One of the attorneys who handled that case said yesterday he is ready to file suit in neighboring counties if they don't take steps to reassess property values in their counties on their own.

Pittsburgh attorney Donald Driscoll, who together with Ira Weiss represented the group of homeowners that mounted the case against Allegheny County's base-year plan, said he's prepared to file suits against other counties like Beaver, Butler, Washington and Westmoreland.

"We are going to start seeking referrals in these counties and we will offer our representation to homeowners there who are struggling with lowered property values. Then we will bring against them the same case we brought against Allegheny County," said Mr. Driscoll.

The court ruled that counties can't use a base-year assessment system, where property values are based on construction costs in a previous year, without reviewing and updating the system to address changes that occur over time as neighborhoods show growth or decline. The court said it is unconstitutional not to make adjustments, and most counties have no regular method of checking for disparities.

An attorney with the Community Justice Project, which is part of the Pennsylvania Legal Aid Network, Mr. Driscoll said that based on the benchmarks the Supreme Court established in its Allegheny County ruling, "the vast majority of Pennsylvania counties using a base-year system have a non-uniform assessment system, which the court said is unconstitutional."

But some officials in surrounding counties say they don't need Mr. Driscoll to tell them what they now know, particularly after the court's ruling on Allegheny's base-year assessment system.

"We all know the writing is on the wall and that we were going to have to do [a reassessment] at some point," said Westmoreland County Commissioner Charles Anderson.

The county, which last did a full-scale reassessment in 1973, is in the process of putting together a reassessment plan, even though no schedule has been determined yet, Mr. Anderson said.

In Washington County, where officials have not done a reassessment since 1981, Commissioner Lawrence Maggi said the county already is planning a court-ordered reassessment for 2012.

"We have been anxiously waiting for the Allegheny County decision because we thought it would affect our plans," he said. "Our solicitor tells us it doesn't so we are going to proceed with our plan."

Washington County Court of Common Pleas Judge Debbie O'Dell Seneca last year ordered the county to reassess its property values after two school districts sued the county over the inequity of its base-year assessment system.

"We're taking a look at [the Supreme Court ruling], said Dale Pinkerton, commissioners' chairman in Butler County, which last reassessed its property values in 1969. "We're going to have our solicitor examine it and then see if there's anything we need to do."

Officials in Beaver County, which last reassessed in 1982, could not be reached for comment.

Douglas Hill, executive director of the County Commissioners Association of Pennsylvania, said Wednesday's decision doesn't mandate that other counties do reassessments, but it does point out that many may be vulnerable to a legal challenge.

"I would concede that some of the counties that haven't reassessed for many years could be in trouble," he said. "As they are challenged, they will look at it and see whether they have to reassess and many of them will."

Although many see political considerations as the main reason some counties don't reassess, Mr. Hill said the biggest stumbling block is the cost. He estimated that it costs $75 to $125 to assess each property, which would place the cost for about 82,000 parcels in Westmoreland County at $6.1 million to $10.2 million.

"The counties will need some help to do this," Mr. Hill said. They would look for state funds to help pay for reassessments, he added, noting that the state also is facing a possible $3 billion deficit this year.

In addition, now that there is a decision in the Allegheny County case, Mr. Hill said the association will ask the state Local Government Commission to recodify assessment laws for all counties except Allegheny and Philadelphia so that they all follow the same rules. Then it would be easier to deal with assessment issues as a group.

Meanwhile, the Supreme Court's decision gives more fodder to organizations such as Stop Taxing Our Property, which wants to eliminate property taxes.

"If this decision affects only Allegheny County, all it will take is someone filing suit in the other counties about the unconstitutionality of the base-year system in your county and the result will likely be the same," said Bob Logue, spokesman for the group.

Allegheny County Executive Dan Onorato is formulating the county's response to the court ruling and has vowed not to perform a reassessment.