Well, 32 years ago.  Here is the story – straight from the “horses mouth:”

During 1981, an incident involving the importation of mislabeled and adulterated meat from Australia resulted in FSIS detaining and sampling nearly 66 million pounds of boneless beef from that country. Shipments labeled as beef were found to contain horsemeat and kangaroo meat. The problem was traced to plants in the State of Victoria, and most of the product has been cleared and allowed to enter U.S. commercial channels. To prevent a similar occurrence in the future, FSIS is implementing a comprehensive program to strengthen controls on meat imports.

In July, an FSIS inspector retained and sampled three frozen blocks of boneless beef, based on their abnormal appearance. Tests confirmed that horsemeat had been substituted for beef. With the aid of the Australian Government, FSIS traced the problem to a meat substitution scandal in the State of Victoria, operating outside the controls of Australia’s Federal inspection system.

When the problem first became known, FSIS asked USDA’s Office of the Inspector General (DIG) to investigate the matter. Also, FSIS set up an internal Board of Inquiry to examine the Agency’s response to the incident as well as the adequacy of U.S. import inspection laws, procedures, and policies.

In August, after laboratory tests confirmed that adulterated shipments from the Australian plant in question had entered the United States as early as January 1981, Secretary of Agriculture John Block announced a series of steps to prevent mislabeled, uninspected, or otherwise adulterated meat from entering this country. The first step—the impoundment and testing of all Australian boneless beef in this country—was designed to determine if the problem was more widespread. Within several days, FSIS had located nearly 66 million pounds of the product.

Other steps outlined by the Secretary included 1) requiring Australia to begin a species testing program on exports of boneless meat to the United States and to keep the meat under security until it reached this country; 2) holding Australian boneless meat at U.S. ports until its species was confirmed; 3) requiring other exporting countries to initiate a species testing program; 4) spot-checking for species all boneless meat entering U.S. ports; and 5) reviewing compliance activities in major exporting countries.

FSIS released most of the impounded meat on September 4. Product from Victoria—representing about 19 percent of the impounded Australian product—remained under U.S. control because FSIS found horsemeat in product from a second plant in that State. All incoming Victoria product became subject to intensified inspection, while other Australian product was handled under an interim species-monitoring program at U.S. ports. FSIS sampled the Victoria product on a plant-by-plant basis, and as tests on a firm’s product confirmed its species as beef, the meat was allowed to enter U.S. commercial channels.

Throughout the incident, FSIS laboratories conducted 1,800 species determination tests on samples of Australian product. To increase species testing capabilities, the Agency set up an Accredited Laboratory Program, which allowed private laboratories to perform the tests. FSIS is studying methods to expand and improve methods for species determination.

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