With the exception of infant formula, the laws that the Food and Drug Administration administers do not preclude the sale of food that is past the expiration date indicated on the label. FDA does not require food firms to place "expired by", "use by" or "best before" dates on food products. This information is entirely at the discretion of the manufacturer.
A principle of U.S. food law is that foods in U.S. commerce must be wholesome and fit for consumption. A "best by", "use by" or expiration date does not relieve a firm from this obligation. A product that is dangerous to consumers would be subject to potential action by FDA to remove it from commerce regardless of any date printed on a label.
FDA reminds consumers that if they are in any doubt about the fitness of a food product, whether based on a label date or any other factor such as smell or appearance, its best to simply throw it out.