de son tort trustee

Person who is not a party to a trust agreement (and has no authority as a trustee) but meddles with the trust property or takes upon himself or herself to carry out acts characteristic of the office of trustee. Instead of prosecuting this person, the courts may hold him or her to be a constructive trustee and, thereby, impose the liabilities of an actual trustee in accounting for his or her acts. 'De son tort' is Latin for, by his (her) own wrongdoing.