What is the standard of review for a jury to view evidence of a defendant's oral confession with caution?

"When the evidence warrants, the court must instruct the jury sua sponte to view evidence of a defendant's oral admissions or confession with caution." (People v. Dickey (2005) 35 Cal.4th 884, 905.) As the People recognize, the court's failure to do so in this case was error. That error, however, was harmless.

The standard of review for failing to give the required cautionary instruction is "the normal standard of review for state law error: whether it is reasonably probable the jury would have reached a result more favorable to defendant had the instruction been given." (People v. Carpenter (1997) 15 Cal.4th 312, 393.)