A transaction that was completed by a capable citizen, but who was in a state in which he could not understand the meaning of his own actions and manage his behavior, can be qualified as invalid. This provision establishes Art. 177 of the Civil Code of the Russian Federation. The decision is made at the suit of the subject whose interests or rights have been violated.
A similar rule applies to transactions concluded by a person subsequently declared legally incapable if evidence is provided that at the time of the commission a citizen could not be aware of the significance of his own actions and control his behavior. In this case, the basis for the proceedings is the lawsuit of the guardian of the specified person. Upon recognition of the invalidity of the transaction in the above situations, the rules established by para. 2 and 3 p. 1 art. 171 of the Code. 
Art. 177 of the Civil Code of the Russian Federation with comments
The considered norm is valid in respect of transactions made by competent entities, which, however, at the time of their conclusion were not able to understand their actions and manage their own behavior. Available under Art. 177 of the Civil Code of the Russian Federation, judicial practice is quite extensive. This type of invalidity of legal relations is considered traditional for the domestic legal system. Transactions described in Art. 177 of the Civil Code of the Russian Federation, qualify as agreements with vices of will.
Base of invalidity
As it is within the meaning of Art. 177 of the Civil Code of the Russian Federation acts the actual insanity (incapacity) of the party to the transaction. As a rule, this condition is temporary. In this, it differs from legal incapacity, discrediting all transactions of the subject. Thus, the actual state can act as the basis for recognizing the invalidity of the agreements only at the moment at which the person could not be aware of his own actions and control the behavior. Practice Art. 177 of the Civil Code of the Russian Federation shows that even one of the above mental defects will be considered sufficient. The provisions of the norm also apply to transactions concluded by entities with limited and partial legal capacity. 
Nuance
Upon recognition of invalidity, the reason due to which the citizen was in an insane state will not matter. It can be caused by circumstances that cannot be blamed on him, and depending on him. The first, for example, can be attributed to a strong psychological trauma, mental pathology, hypnotic state, and so on. In the second case, insanity can be caused by alcohol, drug intoxication. By this Art. 177 of the Civil Code of the Russian Federation differs from Article 178 of the Code, which describes the responsibility of an entity unable to understand the meaning of its own actions for harm. 
Problems of proof
Confirmation of insanity at the time of entry into legal relations is considered the most difficult moment when applying the rule in question. The presence of a subject of mental pathology or another disease, a person in a state of intoxication cannot, by themselves, serve as evidence that, upon signing the agreement, a citizen did not understand the meaning of his own actions and did not control them. The testimony will also be considered insufficient. In cases of this category, in particular concerning contesting a will formulated by entities that do not understand the consequences of their behavior, a medical examination is prescribed. Art.177 of the Civil Code of the Russian Federation requires the study of all factual circumstances, documents, conclusions and other materials that can reliably establish the state of a citizen at the time of transaction. 
Special cases
P. 2, Art. 177 of the Civil Code of the Russian Federation is devoted to transactions of citizens who at the time of the commission were considered legally competent, but already had a mental disorder, which became the basis for the subsequent recognition of incapacity. In fact, the general rules of the rule in question apply to such legal relations. The only difference is that the lawsuit can only be filed by the guardian. In practice, the process of proof in this case is somewhat facilitated. This is due to the fact that the guardian is exempted from the obligation to confirm the presence of dementia or mental pathology in the ward. However, it is necessary to prove that at the time the transaction was completed, actual incapacity was present.
Subjects of law
Both citizens who have committed it and other persons whose interests and rights have been violated can file a lawsuit to challenge the transaction. The latter, in particular, may be relatives of the insane subject, represented (if the person acted as a representative), legal heirs and so on. In any case, they should have a legally significant interest in the dispute. Its presence is subject to proof. In accordance with paragraph 2 of the rule under review, the authorized representative is the guardian who was appointed to the citizen who concluded the transaction in a state of insanity and was subsequently declared legally incapable. However, within the meaning of the article, an application may be filed by any entity whose interests have been violated. 
Controversial moment
It relates to the application of the provisions of Article 177 of the Civil Code of the Russian Federation to transactions concluded by legal entities. They enter into legal relations through their bodies (director, manager, boss, etc.), which are usually citizens. If these entities at the time of the transaction were in a state of insanity, there is a flaw in the will. This, in accordance with the general rule, acts as the basis for the recognition of the disputability of the agreement. Thus, there are no obstacles for the provisions of the rule in question to apply to transactions made by legal entities.
Effects
The recognition of the invalidity of the transaction provides for bilateral restitution. Subjects must return to each other everything that they received. In addition, it provides for compensation for damage caused to an insane citizen. This, however, is only possible if it is proved that the other party was aware of the citizen’s mental disorders, but he nevertheless took advantage of his condition. The provision of supporting materials relates in this case to the obligations of the plaintiff. 
Conclusion
Art. 177 of the Code describes the consequences of transactions with a vice of will. The provisions of the norm can be applied to legal relations in which not only citizens, but also legal entities participate. When considering cases, the courts should carefully study the material presented. This is especially important when deciding on compensation for harm caused to an insane person. In this case, it is necessary to take into account the transaction price, its subject, as well as the specifics of the counterparty.
