Allen raises and trades birds as a vocation. He imported eclectus parrots from a dealer in Singapore, and the birds came from Indonesia. The birds were not allowed to be exported from Indonesia, and neither Allen nor U.S. Customs was aware that this was so. However, U.S. Customs learned of that law and seized the birds under 19 U.S.C. Section 1527 (1976). That statute prohibits the importation of wild birds protected under the laws of a foreign nation. Allen claimed that he had done all required to find out whether Indonesia protected the birds and he had made an innocent mistake. Allen also claimed that the birds were not wild birds since they had been raised in captivity. The United States claimed that any birds found in a wild state are protected under the statute. The court ruled that the statute applied to innocent as well as culpable mistakes and that forfeiture was appropriate. Allen appealed.