Geez...there is so much misinformation posted in this thread that I feel like I am reading at AVS. Read NFPA 70 and take it to heart or be prepared to lose it all one day. Your insurance does not mean anything if you screw up. This is exactly why all states need to require low voltage licenses. You guys throw around terms like plenum CL2 CL3 riser like you actually know what it means. Almost every use that was stated in this thread was incomplete or incorrect.

To answer your question...NO it is not legal in 99% of the US to run lamp cord in walls. The places where it is legal do not have building codes or at least have not adopted NPFA 70.