Comey said he hasn't thought through all the international implications. "I can imagine them saying, 'we as an American domiciled corporation, will comply with ... requests from the U.S. government in connection with lawful investigations,'" he said. "Where we may get is to a place where the U.S., through its Congress says, 'we need to force this on American companies,' and maybe they will take a hit."
Even as the FBI worries about going dark, many Internet and electronic device users are concerned about "going bright," said Cameron Kerry, a former general counsel and acting secretary of the U.S. Department of Commerce. "There's a tremendous amount of digital information that is available to companies and to governments," said Kerry, now a visiting fellow at Brookings.
U.S. policy on access to digital information could drive international norms, Kerry said. "If we go down this road and take steps that would break encryption, what is the impact on more repressive countries around the world that will follow that example?" he said.
Comey's speech also drove an active debate on Twitter. "I oppose requiring companies to build back doors into their products," tweeted Senator Ron Wyden, an Oregon Republican.
Comey gave examples of four investigations, including a child sex abuse case and a child murder, in which he said information from smartphones was significant in getting convictions. If encryption is standard on smartphones, those convictions would be much more difficult, he said.
"I like and believe very much that we need to follow the letter of the law to examine the contents of someone's closet or someone's smartphone," he said. "But the notion that the marketplace could create something that would prevent that closet from ever being opened, even with a properly obtained court order, makes no sense to me."
He called on the country to have a debate about the proper level law enforcement access to communications, after revelations of NSA surveillance may have lead to an overreaction. "Are we so mistrustful of — and of law enforcement — that we are willing to let bad guys walk away, willing to leave victims in search of justice?" he said.
Sign up for Computerworld eNewsletters.