California Code, Revenue and Taxation Code - RTC § 13555

If any personal representative fails to pay any tax imposed by this part for which he or she is liable prior to the delinquent date of the tax, he or she shall, on motion of the Controller, in his or her discretion, be required by the superior court having jurisdiction to execute a bond to the people of the State of California in a penalty of twice the amount of the tax with those sureties as the court may approve, conditioned for the payment of the tax, plus interest on the tax at the rate of 12 percent per annum commencing on the date that tax became delinquent, within a certain time to be fixed by the court and specified in the bond.