P-13.1, r. 5 - Rules of evidence, procedure and practice of the Comité de déontologie policière

Full text
4. Service of a writing, including a subpoena, may be made by regular mail, by registered or certified mail, by bailiff or by any other means that proves the date of receipt.
Service may also be made by a public notice in the newspapers where circumstances so require, in particular when there is an interruption in postal service or it is impossible to locate a witness.
O.C. 908-92, s. 4.