INDIANAPOLIS | Lake County officials say they are seriously considering a legal challenge to a 2003 state law that eased property assessments for the region's largest industries and shifted tax burden to homeowners and smaller businesses.

In Indianapolis Wednesday for a conference of county leaders, Lake County Commissioner Roosevelt Allen Jr. expressed frustration with the options state lawmakers have presented to alleviate soaring property taxes.

Allen said legislators should instead revisit their decision to create a new personal property tax bracket for BP, Mittal Steel and U.S. Steel.

"I strongly believe that it's unconstitutional," Allen said of the 2003 law created by House Bill 1858. "It's my understanding that, after the (legislative) session is over, we're going to challenge it in court -- the constitutionality of it -- because ifs definitely unconstitutional."

Local legislators fought for the 2003 law as a way of putting to rest multiple years of property tax appeals by BP, U.S. Steel and Ispat Inland Inc.. -- now Mittal. And industry officials said the move brought much needed equity to tax system that had long favored Lake County homeowners.

The move, coupled with a statewide reassessment ordered by the Indiana Supreme Court, has led to drastically higher residential tax bills.

House Bill 1858 was expected decreased the big three's assessed property values by nearly $600 million, which Allen said has steered about $60 million a year in local tax burden onto homeowners, landlords and smaller businesses.

"So far it's up to about $240 million that's been shifted," Allen said.

Lake County Council President Elsie Franklin said she had some good property tax dialogue with legislators while in Indianapolis this week. But she confirmed that the county is considering a lawsuit against the 2003 tax law.

"Yes, that is an option," she said. "That is, again, special legislation just for Lake County."

Indiana courts have in some cases invalidated so-called special legislation written to impact only one city or county instead of the entire state. Such legislation doesn't spell out specific localities, but includes strict parameters met only by the intended target.

House Bill 1858, for instance, only applies to oil refineries that produce more than 100,000 barrels a day. BP officials, who couldn't be reached for comment Wednesday, recently cited the 2003 tax law change in announcing a planned $3 billion expansion of the Whiting plant.

"House Bill 1858 was instrumental in our decision to invest literally hundreds of million of dollars in Gary Works," said U.S. Steel spokesman John Armstrong. "Even with House Bill 1858, Gary Works remains our highest taxed operating facility, of any our facilities in the country. Any increase in taxes would seriously jeopardize the competitiveness of our operations in Lake County."