Dear when is a lease agreement illegal?
A lease agreement will be illegal if there is a forged signature or other fraud which establishes that the parties named in the lease did not mean to sign the lease or did not sign the lease.
New York law does not protect a party from the decision not to read the agreement. It sounds that if you had read the lease, you would not have signed the lease. Your decision not to read the lease will not necessarily relieve you from the lawful terms of the lease.
A lease in New York is both a contract and a conveyance of property. Parties to a lease, unless prevented from legally making a contract, are allowed on their own to come to an agreement. New York will not enforce a contract that requires committing a crime or other act that violates law.
New York does not prevent a landlord of a house and a prospective tenant of the house from making an agreement where the tenant is responsible for repairs.
You described a house that violates New York State's Warranty of Habitability. The law does not allow the landlord to cause you to give up your tenant rights guaranteed by the Warranty of Habitability. You cannot sign away those rights. You cannot agree to give up those rights. If your lease stated that you gave up the rights provided in the Warranty of Habitability, that portion of the lease would not be enforced against you.
The statutory Warranty of Habitability) requires that where there is an agreement to rent (lease) property for residential use, that the lease be deemed to provide that the rented premises are fit for human habitation and that there are no conditions in the premises dangerous, detrimental or hazardous to the tenant's life health and safety.
"...New York Real Property - Article 7 - 235-B Warranty of Habitability:
§ 235-b. Warranty of habitability. 1. In every written or oral lease or rental agreement for residential premises the landlord or lessor shall be deemed to covenant and warrant that the premises so leased or rented and all areas used in connection therewith in common with other tenants or residents are fit for human habitation and for the uses reasonably intended by the parties and that the occupants of such premises shall not be subjected to any conditions which would be dangerous, hazardous or detrimental to their life, health or safety. When any such condition has been caused by the misconduct of the tenant or lessee or persons under his direction or control, it shall not constitute a breach of such covenants and warranties.
2. Any agreement by a lessee or tenant of a dwelling waiving or modifying his rights as set forth in this section shall be void as contrary to public policy..."
You may have declared the lease of the house breached at its inception due to the violation of the Warranty of Habitability. You may have claimed that the uninhabitable condition of the house caused a constructive eviction.
You should hire an attorney as soon as possible to help you with this problem affecting your home.
The answer provided to you is in the nature of general information. The general proposition being that you should try to avoid a bad outcome if you can.
You can lease a property in any condition. If you want to withhold rent, or just not pay on the grounds the lease was violated you can do so. However, it sounds like the condition of the property might have been disclosed to you.