Does a police officer have a duty to caution a person that their answers may be used in evidence in a criminal case?

Citing Watt J. in R v. Worall, Dambrot J. in R. v. A.D. stated at para 67: …once a police officer has information that would alert any reasonably competent investigator to the realistic prospect that the death of the deceased may have been associated with an unlawful act committed by a person being questioned by that officer, the officer should tell that person that his or her answers could be used in evidence in a prosecution brought against him, even where that person is neither arrested nor detained. The informational deficit arising from a failure to caution the accused is a consideration when the voluntariness of the statement is considered at trial.