NEWARK (AP) — A Roman Catholic archdiocese in New Jersey and two parishioners are suing the state over a new law that makes it illegal for the archdiocese to sell headstones and monuments at its 11 cemeteries.

A California cemetery (Justin Sullivan/Getty Images)

The suit was filed Monday in federal court in Newark by the Virginia-based Institute for Justice on behalf of the Newark archdiocese and parishioners Emilio Mazza of Edison and Dennis Flynn of Emerson.

In court papers, the group's lawyers argue the law is unconstitutional because they say it is economic protectionism that stemmed from lobbying by the Monument Builders Association of New Jersey.

The archdiocese in 2013 expanded an "inscription-rights program" to help ensure it had funds to care for its cemeteries. Under the program, the archdiocese provides the headstone and retains ownership of the monument.

More than 600 inscription rights have been sold since 2006 with a basic cost of about $1,200 a headstone, the lawsuit claims. The archdiocese also has sold 51 private family mausoleums for approximately $6 million during that period.

The Monument Builders Association filed suit in 2013 in which it said the church's tax-exempt status and relationship with parishioners gave it an unfair advantage.

The group lost after a state judge found it was not illegal for the archdiocese to sell monuments under state law. The ruling withstood an appeal.

The association then turned to the Legislature, which passed a measure in 2014 that made it illegal for a private religious cemetery to provide monuments.

Gov. Chris Christie conditionally vetoed the bill, saying parishioners needed more time to make alternative plans. Lawmakers later agreed with Christie and this year delayed the law's implementation until 2016.

The suit seeks to block its enforcement.

The archdiocese serves approximately 1.3 million Roman Catholics in Essex, Hudson, Union and Bergen counties.

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