If my roommate has paraphernalia do I get arrested?
If you're in a place, or in a space, where a reasonable person can conclude that you are either in actual or constructive possession of paraphernalia you are subject to arrest.
This can be in a car, or in your dormitory room, or in your apartment.
The fact that the paraphernalia is in another room allows you grounds to argue; but not with a cop. Perhaps in front of the jury. Bad place to be.
If your roommate has paraphernalia either it/ he/she goes or you go.