What is the standard of proof required to sustain a claim of suicide in a life insurance claim?

The standard of proof is set forth in Norwood, Life Insurance Law In Canada, 1977, at pp. 281-282 as follows: "Although, as will be noted later, it was once considered that the standard of proof necessary to sustain the burden was along the lines of the standard of proof applicable in criminal proceedings, it may be said that it is now established law that, where the question of suicide under a contract of insurance is in dispute, the burden on the party who is asserting suicide will be satisfied upon the preponderance of probabilities, providing, however, that the court take account of the principle, applicable in civil as well as criminal proceedings, that the graver the charge asserted, the greater the degree of proof required. (Hanes v. Wawanesa Mutual Life Insce. Co., 1963 CanLII 1 (SCC), [1963] S.C.R. 154)." And further at pp. 283-284: "The degree of probability necessary to establish suicide may not be as high as the degree of probability necessary in criminal proceedings, but it has been said that it requires a higher degree of probability than is necessary when the matter in issue in a civil proceeding is not the establishment of an illegal act. Additionally, courts pay high regard to the rule that, although the standard of proof is not the criminal standard, the nature and quality of the evidence must be commensurate with the gravamen of the charge that an illegal act has been committed. (Hanes v. Mutual Life Insce. Co., supra, …)"