FBI Director James Comey this week suggested that the FBI paid more than $1 million to access encrypted data on the iPhone of one of the San Bernardino attackers.
Speaking at a conference in London on Thursday, Comey said the cost of unlocking the phone was "more than I will make in the remainder of this job, which is seven years and four months."
The Washington Post calculated Comey's salary as $185,100 using pay scales for federal employees. That would mean his agency spent at least $1.3 million for the de-encryption method.
Though he did not elaborate further on the exact amount or the third-party tool the FBI purchased, Comey speculated that the publicity surrounding the case contributed to more interest in hacking the specific model of iPhone used.
"All the controversy and attention around the litigation I think stimulated a bit of a marketplace around the world which didn't exist before then for people to try and figure out, could they break into an Apple 5c running iOS 9?" Comey said.
There has been some speculation that the FBI received assistance from Israeli security firm Cellebrite to unlock the phone, but neither party has confirmed that information. More recently, the Post said the FBI hired hackers to do the job.
While Comey said the price was "worth it" for this specific case, he doesn't see the FBI as a routine purchaser of encryption-breaking software. Because the tool is specific to the operating system and hardware of the iPhone 5c, it's "not scalable" as new devices come on the market, he said.
Comey also said that while the FBI has withdrawn its litigation against Apple, he thinks the conversation about encryption should continue. "I hope it doesn't lead people to stop talking about it," Comey said.