DENVER — Bankers should beware of the Obama administration’s newly issued green light for banks doing business with the legal marijuana industry, according to the head of the Colorado Bankers Association. Memos released Friday by the Justice Department and Treasury Department’s Financial Crimes Enforcement Network were intended to give banks leeway to open accounts for marijuana businesses in states like Colorado and Washington that have legalized retail pot. Instead, the guidance “only reinforces and reiterates that banks can be prosecuted for providing accounts to marijuana related businesses,” said the CBA in a Friday statement. “In fact, it is even stronger...