Heck, ours do that anyway without light. I was up really late a couple of weeks ago and the living room window was open - there was crowing going on from multiple pens at 0330. All I could do was just shake my head at our weird chickens.
The idea that roosters crow because of light or the sun coming up is a myth. They crow because of their massive ego! LOL! They will crow at anything that dares makes a sound at night. If the dog barks, they will crow. If sparrow chirps, they will crow. Basically, they see everything that makes a sound as a challenge to their rule and authority and they feel they have to out crow it to make sure that everyone knows that they are the boss. About the only way to keep them from crowing is to put ear plugs on them so that they can't hear. My dad actually did this one time when I was a kid. No joke!
