Despite bankers' varied attitudes about legalizing marijuana, now that it is legal in Colorado, banks are supportive of government efforts to permit financial services for marijuana businesses. However, numerous obstacles prevent banks from serving marijuana businesses and their customers as they conduct legal activities.

Colorado can't regulate or tax an industry for which it cannot track money. Public safety risks associated with cash-heavy businesses cause concern. And, several federal laws preclude banks from serving these businesses, regardless of state law. Only Congress can resolve this.

While recent comments by U.S. Attorney General Eric Holder indicate his plans to issue guidance that would shield banks from being prosecuted for providing accounts to marijuana businesses, he cannot change the fact that marijuana remains illegal at the federal level. Banks are responsible to regulators, most of which are independent from the Executive Branch. The idea of no prosecution is nice but, to banks, regulators have the real power.

The only real solution is for Congress to pass laws that will gave banks more comfort in providing services to marijuana businesses. Elections can bring a change in guidance – and Holder's directive would be the fourth Department of Justice formal position on marijuana in recent years. Put simply: banks need the permanence of law versus changeable guidance.

A number of federal laws now preclude banks from opening accounts related to marijuana. The Controlled Substances Act prohibits everyone, including banks, from dealing with controlled substances or the proceeds from them, like the cash from a pot shop. A bank could be seen as enabling money laundering if it accepts deposits from firms in the marijuana business. The Bank Secrecy Act, anti-money laundering laws, and "know your customer"rules hold banks responsible for a customer's actions -- even if the customer attempts to disguise the true nature of an account or a deposit's origin.

Some bank customers have gone to great lengths to disguise accounts related to marijuana, even spraying deposited cash from "Susie's Cookies" with Febrezeair freshener, for example. But banks, as required by these laws aimed at fighting organized crime and terrorism, are on the lookout for attempts at money laundering and must file Suspicious Activity Reports if anything appears amiss – and pot-related deposits fall in that category. Last year, about 1.6 million SARs were filed in the U.S. and 342 people were sentenced to an average of 40 months in prison as the result. Bankers face criminal and civil penalties should they fail to act on their suspicions. These laws can't simply be swept aside; they are both technically and politically complex.

Regulators can impose various civil money penalties, cease and desist orders, fines and can ban bankers from their careers for life, should they violate federal law.

Don Childears is the president and CEO of the Colorado Bankers Association