It was unusual for Martin Hellman, a professor of electrical engineering at Stanford University, to present two papers on cryptography at the International Symposium on Information Theory in October 1977. Under normal circumstances, Steve Pohlig or Ralph Merkle, the doctoral students who also had worked on the papers, would have given the talks, but on the advice of Stanford's general counsel, it was Hellman who spoke.
The reason for the caution was that an employee of the U.S. National Security Agency, J.A. Meyer, had claimed publicly discussing their new approach to encryption would violate U.S. law prohibiting the export of weapons to other countries. Stanford's lawyer did not agree with that interpretation of the law, but told Hellman it would be easier for him to defend a Stanford employee than it would be to defend graduate students, so he recommended Hellman give the talk instead.