Critics of Apple's position suggested the company is ignoring public safety issues.
Apple and Google, by enabling encryption by default on smartphones running their OSes, are, in effect, setting a U.S. policy that values customer privacy over national security and criminal prosecutions, said Cyrus Vance Jr., district attorney for New York County in New York.
Smartphone security and encryption will eventually lead to a serious problem when entire segments of suspects' lives are shielded from police, Comey told lawmakers.
"I have colleagues and others who are advocating for these evidence-free zones," added Representative Trey Gowdy, a South Carolina Republican. "There are just going to be compartments of life where [law enforcement agencies] are precluded from going to find evidence of anything ... no matter how compelling the government's evidence is."
Several other lawmakers questioned the FBI's demands, saying a court order requiring Apple to write new code to defeat the phone's security could lead to hundreds of similar requests. Vance, the New York prosecutor, said his office is now in possession of 205 locked smartphones that could be used as evidence in criminal cases.
Criminals will find ways to exploit mandated holes in encryption, said Representative Zoe Lofgren, a California Democrat. While the FBI worries about "a world where everything is private, it may be that the alternative is nothing is private," she said.
During the hearing, Comey acknowledged the FBI made a mistake when it asked San Bernardino County, the owner of the phone, to change the password soon after the mass shooting there in December.
Comey disputed the suggestion that the FBI was asking for an encryption key or a backdoor into the phone. "There's already a door on that phone," he said. "Essentially, we're asking Apple, 'take the vicious guard dog away, let us pick the lock.'"
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