In a criminal case, the jury must agree unanimously that the defendant is guilty of a specific crime. In a case where the evidence suggests more than one discrete crime, either the prosecution must elect among the crimes or the court must require the jury to agree on the same criminal act. This prevents a conviction based on an amalgamation of evidence of multiple offenses, none of which has been proven beyond a reasonable doubt. In this case, appellant was observed at mailboxes that were later determined to be rifled. Stolen mail from another location was found in the stolen car in which he was a passenger. Appellant was charged with one count of receiving stolen property and one count of petty theft with a prior. The prosecution argued that appellant committed two thefts – one from the mailbox and theft of the items in the car, but did not make an election as to which act was the charged theft. The same was true of the receiving charge. The court failed to give a unanimity instruction. As unanimity could not be assured on either conviction, the judgment was ordered reversed because of this “most common of instructional error in criminal cases.”