California Penal Code 1023 - Interpretation
Section 1023 provides:
"When the defendant is convicted or acquitted or has been once placed in jeopardy upon an accusatory pleading, the conviction, acquittal, or jeopardy is a bar to another prosecution for the offense charged in such accusatory pleading, or for an attempt to commit the same, or for an offense necessarily included therein, of which he might have been convicted under that accusatory pleading."
In People v. Fields (1996) 13 Cal.4th 289, the California Supreme Court concluded that, under both the federal and state Constitutions, when a jury deadlocks on a greater offense but returns a verdict of conviction on a lesser offense, the legal necessity doctrine prevails and retrial of the greater offense is not barred. (Id. at pp. 299, 302-303.)
However, the court further held that retrial is nevertheless barred by section 1023. (Fields, supra, at p. 307.) Although section 1023 does not mention greater offenses, the Fields court concluded that section 1023 expressly bars retrial for the same offense, and a later conviction for a greater offense necessarily includes a conviction for any lesser included offenses, including the one for which the defendant had already been convicted. (Fields, supra, at p. 306.)
The court reasoned that permitting retrial of a greater offense would permit the state to begin with prosecution of a lesser offense and proceed up the scale. (Id. at p. 307.)