Qui Facit Per Alium Facit Per Se Legal Definition: Latin: he who acts through another, acts himself. A fundamental premise of agency law. As stated in Colonial Securities Inc. v. Merrill Lynch, the US District Court referred to, in 1978, the: "... common law maxim qui facit per alium facit per se, he who acts through another acts himself operates to make the acts of an agent within the scope of his authority, in legal effect, the acts of his principal." In Pennsylvania v International Union of Operating Engineers at 469 F. Supp. 329, the US District Court wrote (1978), in reference to the related term respondent superior: "Respondeat superior, a doctrine centuries old, is predicated on the assumption that a master, employer, or principal will be held responsible for the acts of a servant, employee, or agent respectively. The rationale for this view is succinctly expressed by the maxim qui facit per alium facit per se." In Butler v Bunge Corporation (1971), the US District Court adopted these words: "Qui facit per alium facit per se, that is, that the authorized acts of an agent are, in legal contemplation, the same as the principal's acts; and that a principal's tort liability is based, not on an agency relation, but on the relationship of master and servant and is expressed by the maxim. The principle can have far-reaching consequences as succintly put by the Alberta Court of Queen's Bench in Dechant: "... qui facit per alium facit per se. Simply put, the principal ... is liable personally for the negligence of its agent." References and Further Reading: Butler v Bunge Corporation 329 F. Supp. 47 (1971) Colonial Securities Inc. v. Merrill Lynch 461 F. Supp. 1159 (1978) Dechant v. McKechnie Agency Ltd. 1999 ABQB 734 Categories & Topics: Dictionary of Latin Law Terms Duhaime's Tort and Personal Injury Law Dictionary Unless otherwise noted, this page was written by Lloyd Duhaime of Duhaime.org Always looking up definitions? Save time with our search provider (modern browsers only) If you find an error or omission in Duhaime's Law Dictionary, or if you have suggestion for a legal term, we'd love to hear from you!