Long before there was a Measure A to debate in Napa County, voters in Oregon passed a law with the same idea in mind.

Known as Measure 37, the law is more sweeping than the Napa ballot proposal. The Oregon law, passed by 61 percent of the voters in 2004, allows private property owners to seek compensation from the state if land use laws -- including those passsed before Measure 37 was decided -- hurt private property values.

The Napa County proposal is more limited in key respects: It would take hold only in one county, and does not allow private property owners to seek compensation for laws already on the books.

But both measures stem from concerns about government encroaching on property rights, and seek to swing the pendulum toward landowners.

George Bachich, president of the Napa Valley Land Stewards Alliance, said, "We're not facing the onerous regulations that they had to face (in Oregon), and we're not proposing the radical solution that they had to take. But it's motivated by the same spirit."

More than a year after Measure 37 has passed -- and even after the Oregon Supreme Court upheld the law -- opponents and proponents are still sorting out the consequences.

Opponents of the measure say 2,000 property owners have sought claims worth more than $3 billion against the state of Oregon. Most are not demands for money, but rather for changes in zoning or land uses to allow property owners to maximize the value of their properties.

The overwhelming majority of Oregon's claims are for land designated for farming or forest, and come from individuals or developers who seek to build homes, with many also requesting land divisions as well. Geographically, most claims or requests for development come from the western portion of the state, primarily the Willamette Valley.

Many of the Oregon claims filed with the state's Department of Land Conservation and Development have been referred to other agencies such as those dealing with forestry, transportation and parks.

Like Napa's Measure A, the Oregon law allows officials to waive land use restrictions, allowing the requested use rather than paying the owner for the loss of use of the land.

Bob Stacey, executive director for 1,000 Friends of Oregon, which fought Measure 37, said there are still uncertainties about the impact of Measure 37.

"The on-the-ground affects have not yet been realized," said Stacey. "We're still waiting to see, a year and a half after it first passed."

No monetary claims have been paid and the $3 billion figure is misleading, said Stacey, since many of the claims are based on the predicted value of the land when it's developed, not the true loss or value at the time the regulation is imposed.

The 1,000 Friends group is now helping those who could be adversely affected by Measure 37, such as neighbors of potentially developable properties.

Opponents also point to the possible unintended consequences of the measure. In Oregon, billboard companies are filing claims or assisting landowners where they would like to plant large signs. They claim properties have been devalued by restricting the size and type of signs that can go in.

Stacey, asked about Measure A, sounded a theme becoming famailiar in the Napa Valley as the June 6 election approaches.

"Government should be expected to treat property owners fairly, but it shouldn't have its hands tied trying to do it," he said.

Measure A opponents say the law would tie the county's hands. But proponents point out that the Napa measure also gives county leaders the option of taking proposed land use laws to the ballot. Under Measure A, if voters approve a new county law, private property owners cannot seek compensation.