Forgive me if this has been baked; I'd imagine it has been.
Anyways, the idea here is to form a small tracking bug operational within a ten-mile radius into a counterfeit coin. All small business operators, banks, or other handlers of cash would be liscenced by the governments to hold one such
coin, preferably a large denomination such as a Loonie or Toonie. When a robbery occurs, the unsuspecting thief takes the coin, you get the picutre...
It is absolutely imperative that the coin is found and retrieved so that it does not recycle into circulation. This not so much to counteract inflation as it is to avoid confusion. A small static charge could be created via a capacitor to malfunction all circuitry and render the bug inoperative if it is not retrieved within a set time.
A Google search does yield information on tracking bugs that are tiny, roughly the size of a coin. With some funding, this is entirely feasible. Some might say it's not cost-effective, but then again, if we're shooting radio controlled cars off to Mars for no apparent reason... might as well blow the money on something practical.
As news spreads, I would imagine that robbers would simply demand cash in bills only. Of course, the uncertainty would still be in their minds while they were to rob, and it might discourage just a few more that would not have been discouraged initially.