Be very careful of assuming that if someone's heart is in the right place they'll tend to get things right. They need to know what they're doing. Here's one example, from the Marginal Revolution blog, of what happens when they don't:
"Oakland's recent gun buyback was especially ridiculous. The police offered up to $250 for a gun "no questions asked, no ID required." The first people in line? Two gun dealers from Reno with 60 cheap handguns. Fortunately the buyback did manage to get some guns off the street, too bad they were turned in by a bunch of senior citizens from an assisted living facility. Whew, the streets are safe at last.
[...]
Imagine that instead of guns, the Oakland police decided, for whatever strange reason, to buy back sneakers. The idea of a gun buyback is to reduce the supply of guns in Oakland. Do you think that a sneaker buyback program would reduce the number of people wearing sneakers in Oakland? Of course not.
All that would happen is that people would reach into the back of their closet and sell the police a bunch of old, tired, stinky sneakers.
Gun buybacks won't reduce the number of guns in Oakland. In fact, buybacks may increase the number of guns in Oakland.
Imagine that gun dealers offered a guarantee with every gun: Whenever this gun gets old and wears down, the dealer will buy back the gun for $250.
The dealer's guarantee makes guns more valuable, so people will buy more guns.
But the story is exactly the same when it's the police offering the guarantee. If buyers know that they can sell their old guns in a buyback, they are more likely to buy new guns. Thus the more common that gun buybacks become, the more likely they are to misfire...."