There it is. A district court judgement just out has revealed that the FBI used someone’s cell phone to eavesdrop on conversations held in proximity to the phone. Not ON the phone, in the vicinity of the phone. A cell phone can be tapped at will, used as a “roving bug” as law enforcement calls it, to record and transmit what it hears. The cell phone doesn’t even have to be on.

Software installed by the cellular service providers can turn any cell phone into a roving bug. We knew the phones transmitted our location, we knew the NSA was recording all cell phone conversations, did we know they can record whatever they want to hear from the microphone on your cell phone? And you carry that thing with you everywhere!

Many did know this actually, but now it’s on the record. Now YOU know. And what are you going to do about it? What can you do? The cellular communications companies are not going to act against the interest of the government. They cannot hobble the roving bug software without leaving a counter-measure for the NSA. But the answer may lie in your battery.

Your battery’s charge reflects the activity on your phone. If you are able to go two days on one charge and suddenly you can only go one day, with no change in the demands you’ve placed on the phone, maybe somebody else’s activity is using the extra juice. Perhaps a third party battery maker can design a battery which indicates when it is being tapped for power. You wouldn’t be able to prevent the eavesdropping, but you’d see when it was happening.

Pulling the battery out of your phone will disable eavesdropping, but defeats the utility of your cell phone. A sound-proof shroud to cover your phone might be more practical for times when YOU are not using it. But surveillance evasion, like using encryption such as Pretty Good Privacy, merely telegraphs that you might be a person of interest with something to hide.