Disclaimer: I dont know much about how bitcoin works
It would seem though that one would need a third party transaction 'escrow' (for lack of a better word) which could invalidate bitcoins should they be stolen.
Basically saying "this bitcoin transaction is valid, therefore these bitcoins of value x are valid"
If things are stolen, then you could disable those bicoins.
Invalidating bitcoins would not work though. additionally, it is against the philosophy of bitcoin, basically to be a currency without supervising powers.
You literally have to think of bitcoins like real cash. I know that it feels unnatural at first, as usually everything you do software side on a computer is reversible, but that is not the case with the way bitcoins work. Everyone who runs the bitcoin client validates transactions and when a certain threshold is reached, the transaction is successful.
Therefore, to prevent the validation of transactions, you would have to run an astonishing number of clients which refuse validation.
The only way you could intercept stolen bitcoins at this point is, that the services which you can use to exchange bitcoins to dollars keep a db of stolen coins and prevent those from being cashed out.
It would seem though that one would need a third party transaction 'escrow' (for lack of a better word) which could invalidate bitcoins should they be stolen.
Basically saying "this bitcoin transaction is valid, therefore these bitcoins of value x are valid"
If things are stolen, then you could disable those bicoins.