Françoise Nadon, an intervener in the lower courts representing a class action group seeking ragweed eradication, brought a motion to be substituted or added as a party to contest an application for leave to appeal filed by Canadian Pacific Limited and others.
The respondents, including various municipalities, did not intend to contest the leave application.
The Supreme Court of Canada held that while a private party cannot substitute itself for municipal bodies, Nadon's participation was necessary to fully inform the Court.
The motion was granted in part, authorizing Nadon to file an objection to the application for leave as if she were a respondent.