Section 17

the court is satisfied that such tenant was prohibited by the terms of his tenancy from subletting or that such subtenant has used the premises for illegal or immoral purposes; and

such subtenant has been made a party to the proceedings or has had an opportunity of being heard.

Every order or judgment for possession made against any tenant shall declare whether it shall be enforceable against any subtenant or not.

Any subtenant against whom such judgment or order is not enforceable shall, if he remains in possession after notice of the judgment or order has been served on him, cease to be a subtenant of the tenant and shall hold the premises comprised in the subtenancy subject to any subsisting restrictive covenants contained in the terms and conditions of the tenancy between the landlord and the tenant and to all the rights and powers conferred on a landlord under any law relating to distress for arrears of rent, and shall be entitled to give up possession of the controlled premises only by giving such notice as would have been required under the original subtenancy or if no notice would have been so required on giving not less than one month's notice provided that notwithstanding anything in the contract of tenancy a landlord who obtains such judgment or order shall not be required to give any notice to quit to such subtentant.