(b) Any bilateral or multilateral treaty in force for the State Party concerned. 2. Nothing in the present Convention may be interpreted as implying for any State, group or person any right to engage in any activity or perform any act that would impair any of the rights and freedoms as set forth in the present Convention. Article 82 The rights of migrant workers and members of their families provided for in the present Convention may not be renounced. It shall not be permissible to exert any form of pressure upon migrant workers and members of their families with a view to their relinquishing or forgoing any of the said rights. It shall not be possible to derogate by contract from rights recognized in the present Convention. States Parties shall take appropriate measures to ensure that these principles are respected. Article 83 Each State Party to the present Convention undertakes: (a) To ensure that any person whose rights or freedoms as herein recognized are violated shall have an effective remedy, notwithstanding that the violation has been committed by persons acting in an official capacity; (b) To ensure that any persons seeking such a remedy shall have his or her claim reviewed and decided by competent judicial, administrative or legislative authorities, or by any other competent authority provided for by the legal system of the State, and to develop the possibilities of judicial remedy; (c) To ensure that the competent authorities shall enforce such remedies when granted. 138