In 1986, the Federal Food and Drug Administration (FDA) was involved in nearly 1,700 cases of actual tampering or hoaxes. In such incidents, certain principles apply: (1) rarely is a threat to tamper actually carried out, (2) tampering is a copycat crime, (3) nearly two-thirds of the threats are directed at retail stores, (4) products threatened are usually well-known national brands, and (5) there is no such thing as a 'tamper-proof' package. Offenses include fake tampering cases, false allegations of tampering, threats to tamper, and product seeding (false reports by consumers that they were harmed by foreign objects in a product). Tamperers are adult offenders who are ordinary criminals and con artists who commit offenses for profit, revenge, thrills, and other reasons. The Federal law regarding tampering, enacted by Congress after the Chicago Tylenol murders of 1982, carries fines of up to $250,000 and prison terms ranging from 5 years to life. Allies in the investigation of tampering include local authorities, the FDA, U.S. Department of Agriculture, and the manufacturer of the product. Investigation includes determining where and when the product was manufactured and to which part of the country it was distributed. Also used are tape recordings of threats and other suspicious communication, and 'repeater' lists of people who have filed numerous complaints about food products.