Colorado has just past a law to legalize recreational marijuana with sales starting January 1, 2014
The article: Colorado’s legal recreational pot industry off to smoking start states that Colorado residents age 21 and over can buy an ounce of marijuana and non-residents can buy a quarter-ounce of marijuana under the new law regulations.
Although if you are a non-resident don’t try to carry it across the state line you could be charged with drug trafficking.
Smoking pot in public is illegal as is smoking cigarettes in public places such as businesses, air planes, restaurants, and hospitals has been prohibited. Although you can smoke cigarettes outside most public places, smoking marijuana should be done in your own private residence.
Never drive after smoking marijuana or drinking for your own safety and the safety of others, also it is illegal.
For more in-depth information go to: 8 Things to know about buying and smoking pot in Colorado