R. v. Lucas, 2014 ONCA 561:
 Informer privilege protects from revelation in court or in public any information that might tend to identify one who gives information related to criminal matters to the police in confidence. Its twin objectives are to protect the informer from possible retribution, and to encourage other potential informers to come forward. The Supreme Court has emphasized that the rationale for the informer privilege rule “requires a privilege which is extremely broad and powerful”: Named Person, at paras. 16-18, 30.
 There is a presumption that any proceeding that might reveal the identity of an informer will be held in camera. As the Supreme Court noted in R. v. Basi, at para. 44: “[w]hile the judge is determining whether the privilege applies, all caution must be taken on the assumption that it does apply” and “[n]o one outside the circle of privilege may access information over which the privilege has been claimed until a judge has determined that the privilege does not exist or that an exception applies”: R. v. Basi, at para. 44