Two members of the Los Angeles County Board of Supervisors have introduced a proposal to add the image of a cross in the county's official seal -- a move likely to reignite a contentious debate that sparked a multi-year legal challenge nearly a decade ago.

Supervisors Michael Antonovich and Don Knabe filed a motion Tuesday to add a cross to the depiction of historic San Gabriel Mission on the emblem that appears on county property, The Los Angeles Times reported.

The seal once featured a tiny gold cross above an image of the Hollywood Bowl. The cross was justified as a historic reference to the area's settlement by Spanish missionaries in the 1700s.

Under threat of legal action by the ACLU Foundation of Southern California, supervisors in 2004 voted 3-2 to remove the cross. The mission was added that year, among other changes to the original 1950s-era seal.

The Los Angeles Times reports that the supervisors' motion notes that the mission was not topped with a cross when it was added to the seal during the 2004 redesign. The actual cross, which had been removed during an earthquake retrofitting, was returned four years ago.

"The current rendering of the Mission on the seal is artistically and architecturally inaccurate," the motion reads, adding that the cross should be added "in order to accurately reflect the cultural and historical role that the Mission played in the development of the Los Angeles County region."

The Washington, D.C.-based Americans United for Separation of Church and State recently called on the city of DeLand, Fla., to remove a cross from its 131-year-old city seal, arguing that the symbol promotes "Christian theological virtues."

The ACLU vowed to fight any effort to add a cross to the LA county seal, according to the Los Angeles Times report.

"The county's greatest strength is its diversity, religious and otherwise," Mark Rosenbaum, chief counsel of the ACLU of Southern California, told the newspaper. "Placing a cross, the universal symbol of Christianity, back on the seal communicates that L.A. County favors one religion above all others and above the decision not to practice any."

The Associated Press contributed to this report.

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