Does a promise of leniency by the police make a confession involuntary?

Even if the police improperly convey a promise of leniency, that fact by itself does not necessarily render a confession involuntary. Instead, "an improper promise of leniency does not render a statement involuntary unless, given all the circumstances, the promise was a motivating factor in the giving of the statement." (People v. Vasila, supra, 38 Cal.App.4th at p. 874.) Consequently, we are called to consider whether defendant confessed as a result of a promise of leniency.