U.S. Attorney Won't Prosecute Author of Computer Encryption Program By ELIZABETH WEISE= AP Cyberspace Writer= SAN FRANCISCO (AP) - A software writer won't be prosecuted for a program he wrote that was put on the Internet and is now widely used by computer users to keep their communications secret, the government said Thursday. Philip Zimmermann's Pretty Good Privacy encryption program turns computer messages into a jumble of numbers and letters unreadable to anyone except the intended recipient. The code is so unbreakable that it is classified as munitions under the Arms Export Control Act, making its export without a license a felony. Federal prosecutors began investigating Zimmerman in 1993 after the program appeared on the Internet global computer network. Zimmerman said that others put it there, not him. The government opposes export of cryptographic technology for fear it will make it harder to monitor electronic communications overseas, and domestic law enforcement agencies are concerned such programs could keep them from eavesdropping on digital conversations. U.S. Attorney Michael J. Yamaguchi announced the decision not to prosecute Zimmerman, but didn't say why. If convicted, Zimmermann would have faced 51 months in prison. ``I'm just really pleased that the sword of Damocles is not over me anymore and I wonder why it took so long,'' Zimmermann said in a phone interview from his home in Boulder, Colorado. ``This is not just for spies anymore. It's for the rest of us. The information age is here. The rest of us need cryptography to conduct our business.'' The case had been closely watched as computer users and the government square off over free speech and privacy rights. Some critics contended it was foolish of the government to claim that Zimmerman had broken the law because the same coding information forbidden for export electronically may be shipped abroad in print form. They also noted that the technology already circulates throughout the world, making the law unenforceable. ``Zimmermann never exported Pretty Good Privacy, so the U.S. Attorney seemed to be missing the point. Unfortunately there still is no clear ruling from our government as to whether or not making software available on the Internet counts as exporting it,'' said Simson Garfinkel, who wrote a book about the program. Zimmerman's supporters argued that without encryption, government could do widespread eavesdropping, perhaps for political reasons, scanning for words and phrases it considers subversive. They acknowledge that a few criminals may use programs like PGP to hide out in cyberspace, but believe that concern is outweighed by free speech and privacy rights. ``The case was part of the government effort to crack down on good technologies for privacy. We hope the government's decision signals a rethinking of federal policy in this very important area,'' said Marc Rotenberg of the Electronic Privacy Information Center in Washington, an on-line civil rights watchdog group. Others see the 2.5-year investigation of Zimmermann as intimidation. ``It seems to me is that all the U.S. Attorney is saying is that they don't want the public relations nightmare of prosecuting Philip Zimmermann, but they still want everyone scared so that they won't exercise their Constitutional rights,'' Garfinkel said. --- Pretty Good Privacy is available on the World Wide Web at http://www.epic.org/privacy/tools.html