The U.S. Department of Agriculture is trying to find out how Rancho Feeding Corporation of Petaluma put out the meat, which it called "unfit for human food." Investigators now believe the plant was buying diseased cows and processing them when government inspectors weren't there -- hiding the warning signs of cancer by trimming off diseased parts.
CNN has uncovered that one of the government inspectors responsible for protecting consumers from bad meat was having an affair with a plant foreman. One of Rancho's former owners says the relationship was not connected to the recall.
There have been no reports that the meat from Rancho sickened anyone.
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