Allegheny County Executive Dan Onorato yesterday petitioned the Pennsylvania Supreme Court to temporarily stay its order requiring the county to conduct a property reassessment.

"Pennsylvania's property assessment system is broken, and we need Harrisburg to pass uniform, fair legislation to protect homeowners in all 67 counties," Mr. Onorato said.

The state Supreme Court last month threw out Allegheny County's base-year property assessment system, which sets assessments based on the value of property in 2002, including new construction. The court said the system, which Mr. Onorato implemented in 2005, is inherently unconstitutional because it is unfair for property owners with stagnant or falling values.

By not checking assessments at regular intervals, the court ruled, homeowners in communities with declining values pay more than they should, while those in neighborhoods with increasing values pay less than they should.

Therefore, the court ordered Allegheny County Common Pleas Judge R. Stanton Wettick Jr. to set a time frame for a county-wide reassessment to be completed.

Judge Wettick, who early this month met privately with attorneys for the county and property owners who challenged the county's assessment system, has set a hearing for June 3.

Many Pennsylvania counties choose a base year for property assessments and adjust the value of all property to the value it would have had in the base year. That value then is used to calculate how much a property owner pays in real estate taxes.

But Mr. Onorato, who has consistently complained that Allegheny County is being held to a double standard because it uses the same property assessment system as surrounding counties, has since sought to portray the assessment mess in Allegheny County as a state problem, which must be fixed by the Legislature.

"During these difficult economic times, families across Pennsylvania are worried that unfair property tax increases will make it even harder to stay in their homes," Mr. Onorato said.

"Consensus is building in Harrisburg to address the property assessment issue through legislation, and we are asking the court to give the General Assembly time to act on that legislation," he added.

In the petition filed with the Supreme Court yesterday, Mr. Onorato is seeking a 180-day stay to allow the Legislature to address the state's property assessment system.

But Pittsburgh attorney Ira Weiss, who together with Donald Driscoll represented the homeowners that challenged the base-year plan, said the county's latest move is a desperate attempt to delay the inevitable.

"This is more of the same. The county's petition is just a desire to extend this case as long as possible. Certainly, the manner of filing a petition in the waning hours of the week before a holiday, speaks to [the county's] desire to do things when no one is looking," said Mr. Weiss.

He and Mr. Driscoll, he added, plan to file a counter petition with the Supreme Court "as soon as we can."