Although it may initially seem stupid it does make sense. I seggust all UN delegates go out and vote for it
http://www.nationstates.net/cgi-bin/index.cgi/83734/page=UN_proposal/start=
THEIVER IS A GOOD THING
The initial concept is on the face of it absurd - to a point.
However, it would probably be a good idea to set up rules of conduct by which we could decide when people did and did not have to give back things they stole.
For example, the nation of Hooglastahn was once part of an overseas empire. We have, in effect, stolen the entire country from its former owners. We also have no intention of ever giving it back, and have holidays to celebrate this fact where we drink until our vision and coordination is lacking and then play with explosives.
Before that, there were other peoples who lived on this land, which the overseas empire displaced. The owners of this land which we stole it from were themselves thieves and this land has even more former owners - though they are of course long dead.
But their descendents are not. If for some reason we recognized inheritance of property we would have to concede that these lands have rightful owners living somewhere on the continent. And they aren't going to get our country either - and we have holidays to celebrate that fact as well where we eat ourselves sick and argue with our parents.
Theft is a part of Nationbuilding, and needs formal recognition as such.
However, I can't actually find your proposal, so I can't read what it says or endorse it.
Don't make me come over there.
Lord Ventinari of Palin makes note that since the institution of the Theives Guild, and with citizens carrying their mugging card to show that they have already paid their dues for that year, that the hospitals are less crowded, populated more now by unlicensed and unguilded theives than by their victims.
In fact, the police forces are now able to focus on more violent crimes than simple muggings, as the Guild polices transgressors themselves.