Is a confession involuntary if it was elicited by any promise of benefit or leniency?

"'It is well settled that a confession is involuntary and therefore inadmissible if it was elicited by any promise of benefit or leniency whether express or implied. [Citations.] However, mere advice or exhortation by the police that it would be better for the accused to tell the truth when unaccompanied by either a threat or a promise does not render a subsequent confession involuntary.... Thus, "[w]hen the benefit pointed out by the police to a suspect is merely that which flows naturally from a truthful and honest course of conduct," the subsequent statement will not be considered involuntarily made. [Citation.] On the other hand, "if ... the defendant is given to understand that he might reasonably expect benefits in the nature of more lenient treatment at the hands of the police, prosecution or court in consideration of making a statement, even a truthful one, such motivation is deemed to render the statement involuntary and inadmissible...."' [Citation.]" (People v. Holloway (2004) 33 Cal.4th 96, 115.)