Lot's of good posts here. The important thing is to keep this shit in perspective. The popo know you have a grow light and room/closet/hutch/barn/whatever. They aren't stupid, as everyone here has already stated. Now the perspective part: THE WEED FAIRY IS NOT GOING TO COME AND TAKE CARE OF THIS FOR YOU!!!! You've been made by the fuzz and you caught a break. It doesn't matter what you do with the stuff, the cops are on to you. You're just gonna have to lay low, keep your place calm, shoot your roomate, and not grow weed for a few months. The cops will get bored after awhile and find something else to entertain them. Remember, the world of weed is the African Serenghetti. We are the gazelle, the cops are the lions. If you stick with the crowd, they won't even look at you. Stick with the crowd for awhile until some other weak dumbass draws their gaze, then proceed however you want to.
P.S. If it were me in your shoes, I would clean that fucker out!!! Deny everything. Or, better yet, blame it on your stupid roomate.