Q: Two years ago, my wife and I got a roommate to share the rent-stabilized apartment in Manhattan that we’ve lived in for 40 years. A year ago, he stopped paying rent for his room — he didn’t claim job loss or another hardship, he just refused to pay. We do not have a written agreement with him, so we asked him to move out, but he refused. We hired a lawyer, but our claim could not proceed because he applied for the Emergency Rental Assistance Program, and that case is still pending. He has tried to verbally intimidate me, and has periodically locked me out of my apartment. The police have come a few times but have taken no action. What can we do?

A: Normally, in New York, if you want a roommate to move out, you give him written notice — in this case 90 days, because he’s been there for two years and you do not have a written agreement. If he does not comply, you can take him to housing court after the deadline. But because your roommate applied for rental assistance, you have to wait for that case to resolve itself in the courts before you can proceed. So you’re in a holding pattern.

But this relationship is deteriorating into an unstable living environment. “Unfortunately, in my 35 years of experience as an attorney, hostile habitancy arrangements like this tend to escalate from bad to worse,” said Lucas A. Ferrara, an adjunct professor at New York Law School and co-author of “Landlord and Tenant Practice in New York.”

As toxic as the relationship is, see if you can negotiate a settlement. Contact a mediator, like the New York Peace Institute, which offers free support for New Yorkers in Manhattan and Brooklyn. The organization may be able to help you and your roommate reach an agreement that restores calm in your home. You do have some leverage here: He owes you a considerable amount of money for unpaid rent. You could offer to waive that debt and forfeit any chance to take him to small-claims court later, if he agrees to move out. Yes, you’ve lost money, but legal fees are not cheap and your peace of mind is valuable.

There are other legal avenues to pursue. If you and your wife are concerned for your immediate safety, speak with your lawyer about obtaining a restraining order, which may help remove the roommate from the apartment. Document your interactions with him, and keep any police records that you have, to help bolster your claim.

And as soon as the rental assistance case is resolved, hand him his notice to vacate.

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