LOUISVILLE, Ky. — The Archdiocese of Louisville is suing the city's government, contending that it is interfering with religious freedom by refusing to allow buildings to be torn down to make way for church parking.

Louisville blocked plans to provide space for parking across a street from St. Martin of Tours parish by granting landmark status to the church-owned buildings, once home to Tonini Church Supply Company.

The lawsuit was filed last month in U.S. District Court and an expert on religious freedom said the archdiocese makes a strong case.

"As prosaic as parking is, it's essential for the church to function," said Charles Haynes, senior scholar for the Freedom Forum's First Amendment Center in Arlington, Va.

At the same time the archdiocese is filing suit, it is negotiating with the city's housing authority for a possible sale of the Tonini property and some adjacent buildings.

All of the buildings have landmark status, but a deal would allow the authority to refurbish the buildings for first-floor storefronts, which could be leased out, said Tim Barry, director of the Housing Authority. The apartments above them might be where some Clarksdale public housing complex residents might be relocated, Barry said.

Archdiocese attorney Paul Whitty said the lawsuit was filed even as talks with the city continue. The statute of limitations was about to run out and the option of using court action to get use of the property as parking would be lost should the negotiations fail.

If the lawsuit goes to trial, it "will be a good test" of a 2000 federal law that requires governments to show a compelling reason why a church's rights should be limited, Haynes said.

The Religious Land Use and Institutionalized Persons Act — also called RLUIPA — is the latest effort by Congress to protect religious freedom against excessive land-use restrictions, he said.

Anthony Picarello, an attorney for a Washington law firm that specializes in religious-freedom cases, agreed with Haynes, calling parking a legitimate issue in the context of the First Amendment right to religious assembly.

"The way people assemble these days is by car," said Picarello, vice president and general counsel of the Becket Fund for Religious Liberty.

Showing that fewer people would worship at the church without the parking would help the claim, Picarello said.

"A great way to kill a church is to cut off its parking," he said.

The Becket Fund is handling about 10 active cases nationwide under RLUIPA and is providing advice about or has filed briefs of support in about 20 other cases, said Picarello. Those cases are all at various stages of the legal process. The U.S. Supreme Court has yet to agree to hear a case on the religious liberty act, Picarello said.

According to the Louisville lawsuit, the Tonini buildings were donated to the archdiocese in 1994. In 2001, the archdiocese bought the neighboring property, which it uses for one of its programs. In 2002, the church sought a permit to demolish the Tonini property.

But a government commission granted landmark status to the archdiocese's buildings at the urging of the Phoenix Hill Association, which argued that the buildings were once the commercial anchor of the area.

In its suit, the archdiocese argues that the Tonini buildings, one of which was built in 1869 and the other in 1880, have deteriorated to the point that saving them isn't financially feasible. The archdiocese also argues that the standards the city uses to designate structures as landmarks are arbitrary and "further imposed a substantial burden on the religious exercise of the Archdiocese, St. Martin and St. Martin's members."

The archdiocese's suit says parking space is crucial if St. Martin is to continue to carry out its role in the Catholic community. Of its nearly 1,400 regular and associate members, the lawsuit says, only about a dozen families live in the neighborhood.

"The fact that St. Martin is a parish of choice makes it a fragile parish, as members who choose to attend St. Martin can easily choose to go elsewhere if their spiritual needs are not met, or if too many barriers are placed in their way," the suit says.