ALTO PASS, Ill. (CBS) — Atheist activist Rob Sherman says the U.S. Supreme Court is his last chance to block public funding for repair of a massive cross in Southern Illinois.

As WBBM Newsradio’s John Cody reports, Sherman says he has filed his appeal in Washington, D.C., now that the Chicago-based 7th Circuit Court of Appeals has refused to intervene in the case of the cross on Bald Knob.

LISTEN: WBBM Newsradio’s John Cody reports

“The Illinois General Assembly gave Friends of the Cross a $20,000 grant to rebuild the cross, and my issue is that we’re not paying taxes for the purpose of rebuilding Christian crosses or other religious imagery,” Sherman said.

A federal judge ruled last year that the grant was made by the state’s executive branch and was not a designated legislative “earmark” as Sherman had alleged. The judge also found that the state’s economic-development agency has discretion in how it doles out its money.

Sherman sued in August 2010, arguing that efforts to repair the cross using the $20,000 grant “has the primary effect of advancing a particular religious sect, namely Christianity.” He noted that the money came from a $5 million pot of money that the state Legislature channeled to the Illinois Department of Commerce and Economic Opportunity.

Sherman insisted that the grant was, in fact, a legislative earmark — not a discretionary allocation from the executive branch — and therefore funneled state money to a religious site in violation of the First Amendment’s prohibition against the establishment of religion.

On his Web site, Sherman has pointed out that the state constitution says, “No grant of money shall ever be made by the State for any sectarian purpose.”

He says this conflicts with the Bald Knob Cross of Peace organization, which operates the property where the cross stands, and says in its bylaws, “The purpose of this organization shall be to maintain and develop the Bald Knob Cross monument and its properties in ways that advance and are consistent with the principles and values of the Christian faith, for which the monument stands as an iconic symbol.”

The cross is a concrete structure covered by white porcelain panels and can be seen for miles.

Located about 10 miles south of Carbondale, the cross was built largely thanks to local farmers’ profits from selling pigs. It has been a fixture on the 1,025-foot-high Bald Knob Mountain since 1963, standing sentry standing over forests and the region’s orchards and burgeoning wine country.

Easter services have been held on the mountain since 1937.

Over the decades, the cross and its tiles fell into disrepair, prompting its caretakers’ feverish bid to raise funds for a $500,000 restoration that was completed a year ago.

Sherman has also led a lawsuit to overturn an Illinois law requiring a daily “moment of silence” in the state’s public schools, but last month a judge lifted the injunction blocking that law from taking effect.

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