I remember watching Carte Blanche some years back and they set up a sting operation to catch thieves within the post office. An invisible substance was placed inside various parcels and when combined with another chemical substance (which the investigative team later applied), the result was that whatever had been in contact with the two substances was stained blue and was impossible to remove/wash off. End result was that the guys were busted blue-handed so to speak but were not prosecuted as the whole thing was deemed unconstitutional/racist/insert scapegoat-catchphrase-of-the-day here. This was all also backed up with CCTV footage but it still led to no convictions. So unless the government is serious this time, I don't reckon we'll benefit much from SmartWater.
The other problem is that, in order for this to work, you need suspects to test and that means cops out there doing their job and bringing in suspects.
I still think the key to the whole problem is in effective regulation of the scrap metal dealers. Keep a tight, honest lid on that lot and the problem's solved. Easier said than done though I guess.
