Blocking robocalls from spoofed numbers may soon become easier, as the Federal Communications Commission is preparing to give carriers authority to take more aggressive action against this type of scam call.

The FCC in 2015 made it clear that voice service providers can offer call blocking tools to customers, but commissioners said at the time that more needed to be done about Caller ID spoofing. FCC Chairman Ajit Pai has now scheduled a preliminary vote for March 23 on new rules designed to solve the problem.

"One particularly pernicious category of robocalls is spoofed robocalls—i.e., robocalls where the caller ID is faked, hiding the caller’s true identity," the proposal says. "Fraudsters bombard consumers’ phones at all hours of the day with spoofed robocalls, which in some cases lure consumers into scams (e.g., when a caller claims to be collecting money owed to the Internal Revenue Service) or lead to identity theft."

The proposed rules would let providers "block spoofed robocalls when the spoofed Caller ID can’t possibly be valid." Providers would be able to block numbers that aren't valid under the North American Numbering Plan and block valid numbers that haven't been allocated to any phone company. They'd also be able to block valid numbers that have been allocated to a phone company but haven't been assigned to a subscriber.

The proposal would also codify the FCC's previous guidance that phone companies can block calls when requested by the spoofed number’s subscriber. For example, the IRS can request the blocking of its own numbers. "The spoofed number’s subscriber has a legitimate interest in stopping the spoofed calls—in light of the significant reputational damage and other harms they cause," the FCC said last year.

The upcoming vote on March 23 is for a Notice of Proposed Rulemaking (NPRM), which means the rules won't take effect immediately. The FCC uses NPRMs to seek comment on proposals before issuing final rules.

2.4 billion robocalls a month

Overall, US consumers are receiving 2.4 billion robocalls a month, Pai wrote in a blog post yesterday.

"There is no reason why any legitimate caller should be spoofing an unassigned or invalid phone number," Pai wrote. "It’s just a way for scammers to evade the law." Pai noted that there is already a database that keeps track of all phone numbers, many of which are not being used. But "under the FCC’s current rules, which generally prevent call-blocking, there is not much that carriers can do to stop this," he wrote.

The NPRM and a related Notice of Inquiry also seek comment on how else the FCC might tackle robocalls. For example, the FCC is asking for public comments on "how to address spoofing from internationally-originated numbers, where scammers often hide to avoid US legal processes." The FCC will also ask for comment on how to give phone companies a legal "safe harbor" from call completion obligations when they "rely on objective criteria" to block robocalls and comment on safeguards the FCC should use to minimize blocking of lawful calls.

The FCC's March agenda also includes proposed rules to let prisons and jails use radio-based technology to block the use of contraband cell phones. Inmates sometimes use contraband phones for criminal activity such as running drug operations, blackmailing inmates' relatives, and even to order attacks on prison guards or witnesses in pending court cases, Pai wrote.