Constructive trusts in English law are a form of trust created by the English law courts primarily where the defendant has dealt with property in an "unconscionable manner"—but also in other circumstances. The property is held in "constructive trust" for the harmed party, obliging the defendant to look after it. The main factors that lead to a constructive trust are unconscionable dealings with property, profits from unlawful acts, and unauthorised profits by a fiduciary. Where the owner of a property deals with it in a way that denies or impedes the rights of some other person over that property, the courts may order that owner to hold it in constructive trust. Where someone profits from unlawful acts, such as murder, fraud, or bribery, these profits may also be held in constructive trust. The most common of these is bribery, which requires that the person be in a fiduciary office. Certain offices, such as those of trustee and company director, are always fiduciary offices. Courts may recognise others where the circumstances demand it. Where someone in a fiduciary office makes profits from their duties without the authorisation of that office's beneficiaries, a constructive trust may be imposed on those profits; there is a defence where the beneficiaries have authorised such profits. The justification here is that a person in such an office must avoid conflicts of interest, and be held to account should he fail to do so.
Other types of constructive trust not relating to unconscionable dealings are constructive trusts over property, mutual wills, and arguably secret trusts. Where property is sold or transferred, the signing of an agreement to do so automatically transfers the equitable interest to the buyer or transferee; until the property itself is transferred, it is deemed to be held on constructive trust for the recipient. Mutual wills are irrevocable wills made by multiple people to come into force at the writer's death; similarly, these are also considered constructive trusts. Secret trusts are the subject of much debate over their classification, but one theory holds that they are constructive in nature. Related to constructive trusts are constructive trustees, or trustees de son tort; these are where "one, not being a trustee and not having authority from a trustee, takes upon himself to intermeddle with trust matters or to do acts characteristic of the office of trustee".[1] Where their actions are reckless or dishonest, the court makes that person a constructive trustee, forcing them to account to the beneficiaries for any loss suffered and look after the trust property in their possession.