Guns are wonderful devices, but sometimes they just don't belong. Currently, the two state-of-the-art detection methods for spotting an undesirable concealed weapon involve the use of X-rays, or metal detectors.
Metal detectors can mess with pace makers and hard drives, and will detect any mass of
metal, regardless of whether or not it's a gun. Belt buckles, steel toed boots, jewelery, and prosthetics are mistaken for guns by these systems, making metal detectors little more than the boy who cried wolf.
X-rays can spot a gun, get some idea of what kind of gun it is, and are generally more likely to recognize a gun correctly, with false positives normally being caused by the existence of certain gun-shaped objects, or combinations of objects which resemble guns. X-rays have downsides too though. They invade privacy, by allowing guards to see through your clothing, into your luggage, and get enough of a glimpse inside your body to learn a thing or two about your medical history. Not to mention the fact that anyone who must stand near one long enough will develop cancer.
Both metal detectors, and X-ray machines require expensive equipment, pose health risks, and have little purpose besides detecting weapons.
Something less lethal, more correct, and less invasive to privacy would be desirable. I propose that guns be equipped with RFID tags that have the gun's serial number encoded onto the tag. These tags could then, ideally, be read by existing RFID readers in stores, airports, libraries, etc.
As it is a crime to deface the serial number in any way, a requirement not to tamper with the RFID will already have been written into the laws, and gun identification can get very specific without looking at the naughty underthings of every man, woman, and child who passes by. Knowing the serial number of the gun will identify the exact type of weapon, and without invading privacy at all, can even tell the manufacturer, and the last point of sale. Somewhat more invasive models could relate the purchaser, possibly identifying them as military, law enforcement, Private Investigators, individuals with legal concealed carry licenses, avid hunters, or stolen firearms.
As store RFID readers are already set up as a theft deterrent system, their potential for cutting down on crime will now instantly be expanded, and these gun detection devices have already saturated the modern landscape in unobtrusive form without much added expenditures to infrastructure. Anyone carrying a gun would now be detected at most stores, libraries, and many schools, rather than just at courthouses and airport checkpoints.
Different societies can of course use the gun detection technology differently. In areas where guns are legal, it might be preferable to hook up a computer system, so only stolen gun serial numbers set off the alarms, for example.
As criminals often remove the serial number markings from the firing pins of their guns, this might allow another way to try and recognize the now "anonymous" firearms. In some cases, deactivating the RFID might not seem necessary, or possible to the criminal.
Using RFID will have various other downsides as well. Defeating the technology isn't exactly hard, although it would be illegal, and older guns wouldn't show, unless a vast recall of some sort were issued. Thankfully, individuals with enough forethought to obtain untraceable firearms tend to be somewhat more methodical, and controlled with their killing than the less organized murders.
Yeah, it's kind of a crap idea, but I think it might be of some use.