Avoiding robocalls is easier said than done

Want to know who's to blame for all those annoying robocalls during dinner? Nathan Kingsbury, that's who.

He was the AT&T vice president who signed his name to a 1913 letter pledging that the company would open its network to other phone services. The so-called Kingsbury Commitment settled an antitrust case brought by the federal government and paved the way for the modern phone system.

"Because of Kingsbury, we were able to have more than one phone company," said Eric Burger, a computer science professor and director of Georgetown University's Center for Secure Communications.

"That's a good thing," he said. "But also because of him, AT&T and Verizon are required by law to deliver any call that reaches their networks."

That's one reason robocalls keep getting through. Another is that, thanks to technology that can trick caller ID systems, telemarketers and scammers keep finding sneaky ways to get past your defenses.

The head of the Federal Communications Commission last week proposed new rules intended to cut down on the number of robocalls bothering people.

A key change is to clear up any confusion over whether phone companies are allowed to block robocalls, just as Internet service providers try to block spam e-mail.

Problem solved? Not hardly.

Burger is a former telecom entrepreneur who now specializes in network-security issues. He's about as knowledgeable as anyone regarding what phone companies can and can't do to keep telemarketers and scammers at bay.

It would take legislative or regulatory action to tweak the Kingsbury Commitment and allow carriers to block questionable calls from other phone companies, Burger said.

Until then, a telemarketer or scammer anywhere in the world could use some fly-by-night phone company to gain access to the major networks.

Then there's the even bigger problem of spoofing. This is a practice in which a caller ID system is tricked into thinking that a call is originating from somewhere else.

"The whole point of spoofing is to get you to pick up the phone," Burger said.

And here's the catch: It's not illegal.

The federal Truth in Caller ID Act makes it a crime to use a bogus phone number or caller ID message to commit fraud or cause harm to others. But it's not against the law to engage in what courts have called "non-harmful spoofing."

Consumers aren't entirely helpless. Services such as Nomorobo, PrivacyStar and Truecaller can reduce robocall volume, if your phone company will allow them (you'll need to check).

However, these services rely primarily on blacklists of banned numbers to stop robocalls from getting through. All a clever telemarketer has to do is spoof a different number and he's back in business.