Not only is it easily noticed that there are no lights, other drivers call unlit trailers in all the time - not only would you have to dodge the cops, you'd have other motorists calling the you in and reporting you as a traffic hazard.

Needs functioning running lights, brake lights, and signals. Best to buy a cheap lighting kit if you need to drive at night.

Trust me, you also don't want the liability if someone crashes into your unlit trailer at night and is injured...