Hypothetical Scenario: GPS trackers on all guns.
Fact #1: EM waves do not propogate through conductive materials, e.g. gun safes and aluminum foil.
Fact #2: For GPS position fixes, the antenna must have a clear, unobstructed view of the sky.
Fact #3: To enable tracking, either the position must be logged in the unit continuously, or it must rebroadcast to a base-station located somewhere in the Motherland.
Fact #4: This all requires the guns be continuously plugged in, or run on batteries.
Fact #5: Batteries can run out of power.
Fact #6: Massachusetts politicians are morons.
Ok, now that we have the ground rules laid out, let's say that someone wanted to commit a crime and they needed a gun. We'll have to ignore Facts #4 and #5 because they are inconvenient, however, this won't be the first time politicians ignore facts when making laws.
Moving on, let's say the only guns the guy owned had GPS trackers. All he would have to do to remain untracked is wrap some commonly found Reynold's Wrap when it leaves the safe. The foil would block not only the transmitted GPS signals from the satellite and prevent a position fix, but it would also block transmission should the second part of Fact #3 be true. He would have the alibi that the guns were in his safe and nowhere near the crime scene.
The only logical outcome I can imagine here is to ban aluminum foil, which would work out well considering Fact #6.
