In Carella v. California (1989) 491 U.S. 263, the jury was instructed "first, that a person 'shall be presumed to have embezzled' a vehicle if it is not returned within 5 days of the expiration of the rental agreement; and second, that 'intent to commit theft by fraud is presumed' from failure to return property within 20 days of demand." (Carella, at p. 265.) The United States Supreme Court held that these instructions violated the defendant's due process rights because they imposed mandatory presumptions, which "directly foreclosed independent jury consideration of whether the facts proved established certain elements of the offenses with which Carella was charged." (Carella, at p. 266.) As previously stated, CALCRIM No. 1820 did not impose a mandatory presumption. In Carella, the challenged instructions advised the jury that "'intent to commit theft by fraud is presumed if one who has leased or rented the personal property of another pursuant to a written contract fails to return the personal property to its owner within 20 days after the owner has made written demand by certified or registered mail following the expiration of the lease or rental agreement for return of the property so leased or rented.'. . . 'Whenever any person who has leased or rented a vehicle willfully and intentionally fails to return the vehicle to its owner within five days after the lease or rental agreement has expired, that person shall be presumed to have embezzled the vehicle.'" (Carella, supra, 491 U.S. at p. 264.) The United States Supreme Court held that an instruction based upon section 10855 telling the jury "that a person 'shall be presumed to have embezzled' a vehicle if it is not returned within 5 days of the expiration of the rental agreement" violated the Fourteenth Amendment. (Carella, supra, at pp. 265-266.) The nation's high court observed that "the Due Process Clause of the Fourteenth Amendment denies States the power to deprive the accused of liberty unless the prosecution proves beyond a reasonable doubt every element of the charged offense. Jury instructions relieving States of this burden violate a defendant's due process rights. Such directions subvert the presumption of innocence accorded to accused persons and also invade the truth-finding task assigned solely to juries in criminal cases." (Carella v. California, supra, 491 U.S. at p. 265.) Because the presumption of embezzlement in Carella was phrased as an "explicit and unqualified" command to find the presumed fact if the predicate facts were established, and no other jury instruction explained that the presumption of embezzlement was merely permissive, the instruction violated the Fourteenth Amendment. The court concluded that the mandatory instruction "directly foreclosed independent jury consideration" of whether the proved facts established elements of the crime. The court concluded that the instruction "relieved the State of its burden of proof . . . , namely, proving by evidence every essential element of Carella's crime beyond a reasonable doubt." (Carella v. California, supra, 491 U.S. at p. 266.) In Carella v. California (1989) 491 U.S. 263, the trial court instructed the jury that "'whenever any person who has leased or rented a vehicle wilfully and intentionally fails to return the vehicle to its owner within five days after the lease or rental agreement has expired, that person shall be presumed to have embezzled the vehicle.'" (Id. at p. 264.) This instruction was improper because it was mandatory, rather than permissive. (Id. at pp. 265-266.) The court found two mandatory presumptions unconstitutional. One required that if a rental car was not returned within five days after expiration of the rental agreement, the defendant had embezzled it; the second required the trier of fact to conclude that if rented property was not returned within 20 days of demand, the renter intended to commit theft by fraud.