不正当影响是对英国法上传统胁迫学说的狭隘适用范围的克服,由衡平法本着公平正义的原则发展而来的一种确认合同效力的制度。在英美国家的现实生活中,被影响一方当事人以不正当影响为抗辩理由使合同撤销的案件是存在的。律师与当事人之间所订立的合同,也是属于法律规定的推定的不正当影响关系之一。因此,律师在与当事人订立合同时如何避免给当事人造成不正当影响,就显得十分的重要。 The improper influence is a system of confirming the validity of a contract which is developed from the principle of fairness and justice based on the principle of fairness and justice, which overcomes the narrow scope of application of the traditional coercion theory in English law. In the real life of the Anglo-American countries, there are cases in which one of the parties affected by the contract unfairly defrauded the contract by illegitimate influence. The contract concluded between the lawyer and the parties is also one of the presumptive and improper influences stipulated by law. Therefore, it is very important for lawyers to avoid undue influence on the parties when entering into contracts with the parties.