What is the necessary circumstances for a defendant to be found guilty of two counts of first-degree murder under section 12022.53 of the California Criminal Code?

^4. The necessary circumstances are established if the defendant "has been convicted of more than one offense of murder in the first or second degree." ( 190.2, subd. (a)(3); People v. Souza (2012) 54 Cal.4th 90, 110, fn. 6 [if an aider and abettor is found to have harbored the intent to kill, "a finding of guilt of two murders, at least one of which is first degree murder, conclusively establishes the truth of the special circumstance...."].)

^5. As relevant to counts 1 and 2, under section 12022.53, subdivision (d), a defendant convicted of a qualifying felony who is found to have personally and intentionally discharged a firearm, proximately causing great bodily injury or death, is subject to an additional prison term of 25 years to life. As relevant to counts 3 and 5, under section 12022.53, subdivision (c), a defendant convicted of a qualifying felony who personally and intentionally discharges a firearm is subject to an additional prison term of 20 years. Notwithstanding the facial requirement of personal use, the statute elsewhere imposes vicarious liability on aiders and abettors if such individuals are found to have committed the qualifying offense in violation of section 186.22, subdivision (b). ( 12022.53, subd. (e)(1); People v. Garcia (2002) 28 Cal.4th 1166, 1171.)