Marijuana has been legal in Colorado for years now. However, employers in the state still have the ability to drug test for marijuana and implement a zero-tolerance policy.   

Now, state lawmakers are once again considering a bill that would bar employers from firing workers simply over their cannabis use.   

The bill being introduced would require employers to allow their employees to use medical marijuana on premises during work hours and use recreational marijuana off premises during non-work hours.   

There are exceptions for professions that are dangerous or require certain skills.