(NBC News) -- The topic of legalized marijuana was front and center on Capitol Hill Tuesday as lawmakers worked to sort out conflicts between state and federal laws governing marijuana.
A Senate Judiciary Committee hearing hoped to clarify how states may precede in developing the marijuana industry.
More than 20 states have legalized pot, most for medical purposes.
Two states Colorado and Washington have approved it for recreational use.
Last month the Department of Justice announced it would no longer interfere as Washington and Colorado adopt laws to allow marijuana.
-- Leanne Gregg, NBC News, reports