A California raisin farmer is facing at least $650,000 in fines for defying a Depression-era law that requires him to set aside some of his crop and turn it over to the U.S. government without being compensated.

Marvin Horne of Raisin Valley Farms in Kerman has been breaking the obscure law since 2002 and owes the government 1.2 million pounds of unpaid raisins, which is roughly about the size of his entire harvest for four years, The Washington Post reported.

"I believe in America. And I believe in our Constitution. And I believe that eventually we will be proved right," Horne told the newspaper. "They took our raisins and didn’t pay us for them."

At the center of the dispute is a law passed by Congress in 1937 aimed at protecting impoverished farmers by controlling supply and demand for dried grapes after the Great Depression.

The law established the Fresno, Calif.-based Raisin Administrative Committee, which is allowed to set prices for raisins by determining how much of the crop will be sold domestically.

The committee is overseen by the Department of Agriculture and is allowed to sell off a portion of raisins it collects from farmers for free, according to The Washington Post. It reportedly generated over $65 million in one recent year.

"The hell with the whole mess," Horne told the paper. "It’s like being a serf."

Horne handed over part of his crop to the government-controlled raisin "reserve" until 2002. He has since embarked on a mission to overturn the specific regulation that he has been defying.

Brian Leighton, the lawyer representing Horne, argued in initial hearing before an administrative officer that the program was "basically theft" and violated the Fifth Amendment clause against private property being taken without just compensation, The Post reported.

When Horne's case reached the Supreme Court in June, the justices unanimously ordered a federal appeals court in California to take a new look at claims brought by Horne and his wife, Laura, about the program.

Marvin Horne told The Washington Post that he would likely be liable for about $3 million, including fines and the cash value of raisins, if he loses his case.

"If we lose, we’re bankrupt. We won’t have a pot to piss in," Horne told the paper. "No. I don’t want to even think about it. Would you?"

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The Associated Press contributed to this report.