SAN FRANCISCO—FBI Director James Comey has some phones—650 of them, to be exact—that he’d really, really like to take a look at.

Right now, the FBI can’t read the data on those phones, because it’s encrypted. For Comey, that’s a problem. In remarks to the American Bar Association on Friday, he made it clear this is an issue he intends to bring up before Congress next year.

While nothing other than the election will get politicians’ attention during the next few months, Comey told the audience that he intends to gather data about how the problem of encryption, which he calls “going dark,” is affecting his agents’ work. Then, he’ll present the findings to Congress.