Justice Department pushes to mandate a way to unlock phones

WASHINGTON — Federal law enforcement officials are renewing a push for a legal mandate that tech companies build tools into smartphones and other devices that would allow access to encrypted data in criminal investigations.

FBI and Justice Department officials have been quietly meeting with security researchers who have been working on approaches to provide such ‘‘extraordinary access’’ to encrypted devices, according to people familiar with the talks.

Based on that research, Justice Department officials are convinced that mechanisms allowing access to the data can be engineered without intolerably weakening the devices’ security against hacking. Against that backdrop, law enforcement officials have revived talks inside the executive branch over whether to ask Congress to enact legislation mandating the access mechanisms.

The FBI has been agitating for versions of such a mandate since 2010, complaining that the spreading use of encryption is eroding investigators’ ability to carry out wiretap orders and search warrants — a problem it calls “going dark.” The issue repeatedly flared without resolution under the Obama administration, peaking in 2016, when the government tried to force Apple to help it break into the iPhone of one of the attackers in the terrorist assault in San Bernardino, California.