Prosecutors pressed livestock sellers to acknowledge that an Iowa kosher slaughterhouse was often late with payments as they try to prove the plant broke an 88-year-old agricultural law.

Former Agriprocessors, Inc., manager Sholom Rubashkin faces 91 financial fraud charges, among them allegations that he broke a law in the U.S. Packers and Stockyards Act that mandates purchasers make timely payments to livestock sellers.

Records from the Wisconsin-based Equity Cooperative Livestock Sales Association show that Agriprocessors often mailed a check several days after purchasing cattle.

Equity officials testified on Tuesday that Agriprocessors was often late but always paid in full.

The Postville plant was the site of a major immigration raid in May 2008.

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