Well, a drug conviction would be even more expensive than having to relocate abruptly. You need to let your landlord know what is going on. In writing. Arguably this is "gang-related activity" and your roommates can be evicted for this conduct, but they might not be happy with you if they lost their housing, and that might complicate your life in unpleasant ways. Your roommates are breaching the covenant of quiet enjoyment by dealing/using drugs, and the sooner you get out of this situation, the better.
You would not be "breaking the lease" you would be mitigating your damages in response to your roommate's breach/ Tough situation, but I still think it would be cheaper to leave now rather than wait for the cops to arrest you for being complicit. HJP has a really smart crew of attorneys at the Superior Court in Everett, if you go there in the morning, you may be able to get some personalized advice.
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