Can. 124
§1. For the validity of a juridic act it is required that the act is placed by a qualified person and includes those things which essentially constitute the act itself as well as the formalities and requirements imposed by law for the validity of the act.
§2. A juridic act placed correctly with respect to its external elements is presumed valid.
Can. 125
§1. An act placed out of force inflicted on a person from without, which the person was not able to resist in any way, is considered as never to have taken place.
§2. An act placed out of grave fear, unjustly inflicted, or out of malice is valid unless the law provides otherwise. It can be rescinded, however, through the sentence of a judge, either at the instance of the injured party or of the party’s successors in law, or ex officio.
Can. 126 An act placed out of ignorance or out of error concerning something which constitutes its substance or which amounts to a condition sine qua non is invalid. Otherwise it is valid unless the law makes other provision. An act entered into out of ignorance or error, however, can give rise to a rescissory action according to the norm of law.
Can. 127
§1. When it is established by law that in order to place acts a superior needs the consent or counsel of some college or group of persons, the college or group must be convoked according to the norm of can. 166 unless, when it concerns seeking counsel only, particular or proper law provides otherwise. For such acts to be valid, however, it is required that the consent of an absolute majority of those present is obtained or that the counsel of all is sought.
§2. When it is established by law that in order to place acts a superior needs the consent or counsel of certain persons as individuals:
1. if consent is required, the act of a superior who does not seek the consent of those persons or who acts contrary to the opinion of all or any of them is invalid;
2. if counsel is required, the act of a superior who does not hear those persons is invalid; although not obliged to accept their opinion even if unanimous, a superior is nonetheless not to act contrary to that opinion, especially if unanimous, without a reason which is overriding in the superior’s judgment.
§3. All whose consent or counsel is required are obliged to offer their opinion sincerely and, if the gravity of the affair requires it, to observe secrecy diligently; moreover, the superior can insist upon this obligation.
Can. 128 Whoever illegitimately inflicts damage upon someone by a juridic act or by any other act placed with malice or negligence is obliged to repair the damage inflicted.