What is the test for re-examining an expert's testimony in a criminal case?

in the light most favorable to the judgment to determine whether it contains substantial evidencethat is, evidence that is reasonable, credible, and of solid valuefrom which a reasonable trier of fact could find the defendant guilty beyond a reasonable doubt. [Citation.] We presume every fact in support of the judgment the trier of fact could have reasonably deduced from the evidence. [Citation.] If the circumstances reasonably justify the trier of fact's findings, reversal of the judgment is not warranted simply because the circumstances might also reasonably be reconciled with a contrary finding. [Citation.] 'A reviewing court neither reweighs evidence nor reevaluates a witness's credibility.'" (People v. Albillar, supra, 51 Cal.4th at pp. 59-60.) "To prove a gang allegation, an expert witness may testify about criminal street gangs." (People v. Romero (2006) 140 Cal.App.4th 15, 18.)