Definition of 'Undue Influence'
A situation in which an individual is able to persuade another's decisions due to the relationship between the two parties. In exerting undue influence, the influencing individual is able to gain an advantage. In contract law, a party claiming to be victim of undue influence may be able to void the terms of the agreement.
Investopedia explains 'Undue Influence'
Some relationships, such as one between a patient and a doctor or a parent and a child, are considered to run the risk of undue influence and are legally outlined. The onus in this type of relationship is on the person with influence to prove that he was not using his position to take advantage of the other party.
In other situations, one party, based on previous interactions, can be accused of using the trust of the other party to his advantage.