Silencing the loudmouth cellphone user across the aisle is surely a common fantasy among transit riders. But how often do they fulfill their wish and become peace-and-quiet vigilantes - despite decades-old laws against blocking radio transmissions?
That question was raised by a report last week on NBC's Philadelphia affiliate, which interviewed a rider who acknowledged phone jamming on a city bus, and by a subsequent story on Forbes.com that also quoted unidentified jammers in the New York and Washington areas.
The answer is unclear. Although a spokeswoman for SEPTA, Philadelphia's transit system, said there had been no previous complaints from riders, Forbes called the practice "much more commonplace on the rails in both New York and Washington." In October, the Federal Communications Commission took action against 20 U.S. businesses - including Yapper Zapper of Corona, N.Y., and the Signal Jammer of Los Angeles - that it said were selling illegal jammers online, as sites such as China's Jammerall.com still do.
The enforcements follow a "significant uptick" in jamming complaints over the last several years, according to an FCC official who spoke on condition of anonymity and said most incidents are probably never reported.
"These devices are unlawful, and we have a no-tolerance policy," Michele Ellison, chief of the FCC's enforcement bureau, said in statement saying the agency was investigating the Philadelphia report.
According to NBC10 in Philadelphia, a rider identified as "Eric" said he jammed calls on the bus because he found them irritating and rude.
"I guess I'm taking the law into my own hands, and quite frankly I'm proud of it," said Eric, a balding, bespectacled man that NBC10 tracked down after complaints from a staffer that Forbes identified as writer Teresa Masterson. NBC10 did not respond to requests for comment.
Masterson, identified on NBC10's report only as "Marie," said she became disturbed when she and fellow commuters on the Ardmore-Philadelphia route suddenly lost phone connections - failures appearing to coincide with another rider's pushing buttons on a handheld device.
"How dare you decide that I can't speak to somebody, or I can't use my cellphone?" Masterson asked.
Eric told NBC10 that he was enforcing "a right to privacy - to be left alone."
The FCC's Ellison said jammers such as Eric are taking serious risks, such as blocking a scared teen from calling 911 or an elderly person from placing an urgent medical call. "The price for one person's moment of peace or privacy could very well be the safety and well-being of others," she said.
SEPTA spokeswoman Jerri Williams said the transit system itself wasn't at risk.
"The cellphone jammer that the average person can buy online poses absolutely no threat to our communications," she said.
Explore further: GPS Jamming Devices Pose Many Threats (w/ Video)