A Feb. 10, 2012 photo shows medical marijuana growing in a Matthew Huron owned grow house in Denver. Medical marijuana is legal in 17 states, but the industry has a decidedly black-market aspect _ it’s mostly cash-only. In Colorado, state lawmakers are attempting an end-run around the federal ban by creating a cooperative financial institution for state dispensaries and growers to allow them to store and borrow money. (AP Photo/Ed Andrieski)