It's unlikely. My understanding of Colorado CCW law is that there are only a couple types of places where CCW is prohibited. Theaters are not one of them. Other locations can only prohibit concealed weapons if they employ security personnel and electronic screening at all entrances. So, unless there were guards and metal detectors at all entrances to the theater, then it was not a gun free zone.

Then again, I could be surprised. The notion that weapons were prohibited at Fort Hood certainly never would have occurred to me.

If so, this would be only the second time ever that a public mass shooting with more than three people killed took place where permitted concealed handguns were allowed (the Tuscon massacre being the other).

Edit: It is being reported that the theater was indeed a gun free zone. So, I'm surprised again. I will be watching with interest as the facts unfold to find out the legal factors that allow a movie theater in Colorado to prohibit legal CCW.