Cryptography's Role in Securing the Information Society

Congress asked a committee with security clearances whether the United States should go on restricting cryptography. This is the book-length answer, and it came back no.

The 1994 defense authorization act mandated the study. The National Research Council's Computer Science and Telecommunications Board published it in 1996, edited by Kenneth W. Dam and Herbert S. Lin for the Committee to Study National Cryptography Policy. The members were cleared to read the classified material, then wrote an unclassified report. It runs to 720 pages. It explains how cryptography works, weighs what encryption would cost law enforcement and signals intelligence, and traces how export control had shaped what American companies could sell abroad. A long section reviews the Escrowed Encryption Standard, known outside government as the Clipper chip. The conclusions are blunt. Relax export controls, and pass no law restricting the domestic use of encryption.

Both recommendations were resisted and then largely adopted. Export rules loosened in 1996 and again at the end of the decade, and key escrow was abandoned. The report holds its value for how it argued: in the open, on the record, with the classified evidence in hand. Little else from the crypto wars can say the same.