What is the purpose of dangerous offender proceedings?

In Lyons v. The Queen (1987), 37 C.C.C. (3d), at p. 17 Laforest J. referred to the purpose of dangerous offender proceedings by stating: The Commission thus recommended that the extant legislation be replaced by better tailored —dangerous offender— legislation. Its concerns were reflected in the decision of this court in Hatchwell v. The Queen (1974), 1974 CanLII 203 (SCC), 21 C.C.C. (2d) 201 at p. 206, 54 D.L.R. (3d) 419 at p. 425, [1976] 1 S.C.R. 39 at p. 43, where the present Chief Justice stated: Habitual criminal legislation and preventive detention are primarily designed for the persistent dangerous criminal and not for those with a prolonged record of minor offences against property. The dominant purpose is to protect the public when the past conduct of the criminal demonstrates a propensity for crimes of violence against the person, and there is a real and present danger to life or limb.