Although almost half of the states have adopted some form of marijuana legalization, federal law still prohibits the sale and use of the drug. That dichotomy makes a lot of lawyers nervous. Although the U.S. Department of Justice has said that it will relax enforcement in states that have legalized marijuana in some form, the American Bar Association's model rules of professional conduct bar lawyers from counseling or assisting a client in conduct known to be criminal.

Can attorneys represent clients in a business that may be legal under state law but is illegal under federal law?

State by state, bar associations are grappling with the issue. States that have legalized pot for recreational uses have taken the strongest stands. In 2014, after the Colorado Bar Association held that lawyers could not advise marijuana clients in many common business transactions, the state's Supreme Court approved a new rule that allows lawyers to work with marijuana businesses provided that they advise their clients about federal marijuana laws.