In what circumstances will a defendant be held in a retrial for a second time in the course of questioning by the police?

4 Even when it is the suspect who initiates the renewed conversation with the police, the court must make an independent examination of the uncontradicted facts and will hold an ensuing confession involuntary in the traditional sense if it is found to be the product of improper threats or promises of leniency made by the police during the first interrogation. (See, e. g., People v. McClary (1977) 20 Cal.3d 218, 142 Cal.Rptr. 163, 571 P.2d 620.)