A new “smart gun” computer chip promises to keep police guns from firing if they fall into the wrong hands, using a tiny chip implanted in a police officer’s hand that would match up with a scanning device inside a handgun.

If the officer and gun match, a digital signal unlocks the trigger so it can be fired. But if a child or criminal would get hold of the gun, it would be useless.

Once the technology is accepted, legislation could follow to encourage the use of smart guns.