An agreement of private persons cannot derogate from public right.
Conventio Privatorum Non Potest Publico Juri Derogare is used to denote that a convention of private persons cannot detract from public right. Or in other words it staes that the contracts between two or more parties cannot prevent the applications of general rules of law or render the valid aspects as a contravention of law. It is a settled principal that contracts which are made against law or against good morals have no force. Such contracts are bad in law and cannot be enforced in the court of law. The maxim vel contra bonos mores fiunt also states that it is unquestionably the law that agreements which are made contrary to the laws and the statutes or against good morals have no force. Thus it is concluded that any contracts or agreement made by the parties cannot be on any subject matter which is against public morals or public rights and even if such contracts are made they are not recognised by the law and are not enforceable.
Conventio is a general term which includes all kinds of contracts, treaties, pacts or agreements. It is considered to be an engagement formed between two or more persons having mutual consent and mutual benefit to form the agreement. The term conventio is also used to denote that the agreement is either dissolved or change the one which they had previously formed. Thus the maxim Conventio Privatorum Non Potest Publico Juri Derogare means that an agreement of private persons cannot derogate from public right. In other words the maxim states that any agreement made between two or more parties cannot be against public morality or public rights.
If any a person enters into an agreement with another person to commit the murder of a third person and in return he will be awarded with an amount of money, then such agreements are against the public right and thus unenforceable under the law.
In the case of A. P. Rangaswamy v State of Karnataka and ors. it was observed that when public premises is leased or sold or mortgaged to some persons, it is to be done only under the provisions of law. Leasing the property of the Government or Municipality or Corporation, which is a public property, shall be on the basis of distributive order and the persons of the society from different walks of life should be given an opportunity. When the premises is granted to a particular person, he has to utilise the same and shall also give an opportunity to other persons who are in queue. When an agreement is entered into between the parties in clear terms, the agreement prevails over unless it is alleged that the agreement itself is fraud, or etc. The period of occupation is four years eleven months and the said period had expired and thereafter if there is any continuation, the same shall be only on the basis of renewal of licence or permission by open expression. No such permission is granted or renewal is made, under these circumstances, petitioners have approached this Court which is quite contrary to the agreement entered into. The maxim “Conventio et modus vincunt legem” i.e., A contract and agreement overcome the law; and Conventio privatorum non potest publico juri derogare i.e., An agreement of private persons cannot derogate from public right would apply in all fours to these cases. Under these circumstances, petitions fail and accordingly are liable.
In the case of A.B.C. Laminart Pvt. Ltd. Vs. A.P. Agencies, Salem the Supreme court held (i) that the law of contract only prescribes certain limiting principles within which the parties are free to make their own contracts
(ii) that an agreement enforceable in law is a contract
(iii) that an agreement which purports to oust the jurisdiction of the Court absolutely is contrary to public policy and hence void
(iv) that each of the citizens has the right to have his legal position determined by the ordinary Tribunal except, of course, in a contract where there is an arbitration clause which is valid and binding under the law and when parties to a contract agree as to the jurisdiction to which disputes in respect of the contract shall be subject
(v) that a contract which purports to destroy the right of one or both of the parties to submit questions of law to the Courts is contrary to public policy and is void pro tanto
(vi) that parties cannot by contract oust the ordinary Courts from their jurisdiction
(vii) that if parties should seek, by agreement, to take the law out of the hands of the Courts and put it into the hands of a private tribunal, without any recourse at all to the Courts in cases of error of law, then the agreement is to that extent contrary to public policy and void
(viii) that under Section 23 of the Contract Act the consideration or object of an agreement is lawful, unless it is opposed to public policy
(ix) that every agreement of which the object or consideration is unlawful is void; and
(x) hence, there can be no doubt that an agreement to oust absolutely the jurisdiction of the Court will be unlawful and void being against the public policy.
In Maa Binda Express Carrier and another v. North-East Frontier Railway and others the court held that It is well settled position of law that as per the series of decisions rendered by the Hon’ble Supreme Court of India in the matter of award of contracts, the Government and its agency, have to act reasonably and fairly at all points of time and to that extent the tender has an enforceable right in the court which is competent to examine whether the aggrieved party has been treated unfairly or discriminated against to the detriment of public interest.
Edited by Vigneshwar Ramasubramania
Approved & Published – Sakshi Raje
A. P. Rangaswamy V. State of Karnataka and others, 2016 Indlaw KAR 3138
A.B.C. Laminart Pvt. Ltd. V-. A.P. Agencies, Salem, (1989) 2 SCC 163
 Maa Binda Express Carrier and another v. North-East Frontier Railway and others, (2014) 3 SCC 760