Presto Vivace's Journal: Market for stolen cell phones

Here in DC we are having a crime wave of stolen cell phones (article in Washington Post Express, not onlline). How does the market for stolen cell phones work? As I understand it, if mine were stolen I would notify my provider, who would disable it, thus destroying its resell value. Except clearly it does not work that way, hence the market for stolen phones.

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  Also, since our cell phone providers are clearly tracking our phones, surely they could work with police to recover stolen phones. So why don't they?