The defence of provocation in s. 232 of the Criminal Code is a partial defence. More specifically, it operates as an excuse that has the effect of reducing murder to manslaughter when certain requirements are met: R. v. Tran, 2010 SCC 58,  3 S.C.R. 350, at para. 9; see also R. v. Mayuran, 2012 SCC 31.
 In Tran, Charron J. for the unanimous Supreme Court observed that decisions of that court have variously described the requirements of the defence of provocation in s. 232 as comprising either two, three or four elements: see R. v. Thibert,  1 S.C.R. 37, at para. 4; R. v. Hill,  1 S.C.R. 313 at p. 324; andR. v. Parent, 2001 SCC 30,  1 S.C.R. 761, at para. 10. Charron J. commented, at para. 11, that "[t]hese various formulations do not differ in substance."
 Charron J. expressed the view, at para. 23, that "the requirements of s. 232 are most usefully described as comprising two elements, one objective and the other subjective." She cited with approval the following passage from Cory J.'s majority judgment in Thibert, at para. 4:
First, there must be a wrongful act or insult of such a nature that it is sufficient to deprive an ordinary person of the power of self-control as the objective element. Second, the subjective element requires that the accused act upon that insult on the sudden and before there was time for his passion to cool.
 Charron J. went on to describe the objective and the subjective elements as each being "two-fold". In her words, at paras. 25 and 36:
For the purpose of discussion, the objective element may be viewed as two-fold: (1) there must be a wrongful act or insult; and (2) the wrongful act or insult must be sufficient to deprive an ordinary person of the power of self-control.
The subjective element can also be usefully described as two-fold: (1) the accused must have acted in response to the provocation; and (2) on the sudden before there was time for his or her passion to cool.