The Decibel level has been rising in the argument over how much control the federal government should have over the export of encryption technology. The Senate Commerce Committee held hearings Thursday on a proposal dubbed Pro-CODE (Promotion of Commerce On-line in the Digital Era) that would lift current restrictions on exporting encryption software above a certain level of complexity. The move is opposed strongly by law enforcement and national security authorities, who fear the consequences to their tracking of terrorism or crime if uncrackable cryptography becomes the global standard.

But encryption software – which scrambles a person's computer messages so no one can read them without a key – also is thought by many in the computer industry to be the missing piece that's preventing customers from a full-scale move to the Internet for banking and other confidential transactions, rather than, as now, worrying about the security of their data. They also see it as a market in which the United States maintains a comfortable lead, one that is threatened if domestic encryption makers can't sell their products elsewhere. The makers argue that foreign encryption software will rush in to fill the gap, doing nothing about the uncrackability problem – indeed, making it worse. The administration in turn is pursuing a wider international agreement to maintain controls on cryptology export by all the industrialized nations and has been putting pressure on its colleagues in the Organization for Economic Cooperation and Development, which will rule on the matter in a Paris meeting in September.

Administration officials, including FBI chief Louis Freeh, have been pushing for an alternative policy of "voluntary key escrow" – encryption makers would deposit a key to the code with a neutral third body before exporting the products and could then have access to the codes only by court order, as happens now with wiretapping. Mr. Freeh, testifying at Thursday's hearing in favor of an optional key escrow plan, noted that the point is not to prevent all copies of uncrackable code from going abroad – that's clearly impossible – but to prevent such high-level code from becoming the international standard, with architecture and transmission channels all unreadable to world authorities. To software companies and Internet users who have been clamoring for the right to encrypt as securely as possible, Mr. Freeh and others argue, "the genie is not yet out of the bottle" on "robust," meaning uncrackable, encryption.

It's far from obvious to anyone that an optional escrow plan really can prevent the growth of inaccessible transmissions by international terrorists or criminals. Encryption, if widely used, could conceivably ease some privacy problems concerning who gets to see personal and financial data on individuals – though such data usually are vulnerable to being dug out of storage rather than intercepted in transmission. But neither is it clear that the encryption enthusiasts' desire for free development should take precedence over the tracking of terrorism. At the very least, Congress should be exceedingly cautious about getting out ahead of administration concerns on controls that, once lifted, are hardly reversible.