While attorneys usually represents landlord on evictions for non-payment, they also occasionally represent tenants. The landlord will usually use an attorney because of all of the technical rules which must be complied with to evict someone in the housing court.
Tenants on the other hand will only hire an attorney if they have or think they have a defense to the eviction action. Aside from technical (procedural defenses) the main defense to a non-payment eviction is a claimed breach by the landlord of something called the "implied warranty of habitability". This implied warranty of habitability exists as a matter of law and does not have to be stated in the lease. What this means is that any residential rental property must be safe and "livable". Landlords in residential properties must provide heat, hot water, extermination services, and the like to assure tenants that the premises are fit to live in.
If there are widespread problems of habitability in a building the tenants may and often do band together to compel the landlord to cure or fix the problems or problems. This is sometimes done by the tenants though a tenant association hiring their own lawyer and/or agreeing together that no one will pay rent until the problems are fixed. This is known as a "rent strike". Sometimes the tenants will pay the rent into an escrow account to show their good faith for the court.
I am available for a free no obligation telephone consultation if you have a non-payment case in the NYC Housing Court.