<p>I would ask the roommate to help pay for a replacement, but not expect it to happen. Yes, the roommate is the proximate cause of the problem, but the OP did give in to her. However, I don’t really see this as being substantially different than if the roommate had been in the room and left to sit in the lounge, leaving the room unlocked - in fact as others have pointed out, it is possible whoever took the laptop was aware the room was unlocked.</p>
<p>I would report to the local police as well as the campus authorities - $1000 was stolen, not a petty theft. They might also have some ideas on how to track down the laptop - presumably it has a network card that the thief is not likely to remove or disable. That network card has an identifiable MAC address, and it might be possible to trace when someone logs onto the campus network with your laptop (and even who is doing so).</p>
<p>While I don’t generally subscribe to conspiracy theories, it is also possible that it was taken by one of those young women in the lounge, and the rest of the group covered for her - that would explain their report of a mysterious young man in the dorm wandering around, and why they didn’t report him.</p>
<p>Most crime on campuses is opportunistic in nature - someone leaves their belongings unattended, or their room unlocked. This roommate is naive to think you can simply leave the room unlocked. Perhaps she would feel different if he own belongings went missing.</p>