The largest beef recall in US history – more than 140 million pounds of red meat – was sparked by a covert Humane Society video showing employees at the Westland/Hallmark Meat Co.in Chino, Calif., dragging so-called "downer" cows onto a killing floor. Federal officials determined the cows had not been properly inspected. Although no illnesses were tied to the recall, it sparked changes in food-safety procedures, caused the company to close, and led to the criminal conviction of two employees.
– Geoff Johnson is a Monitor researcher. An earlier version of this story appeared here.