What is the test of the "rule of lenity" in criminal law?

Defendant argues that the rule of lenity requires us to interpret the statute in his favor. " [W]e have repeatedly stated that when a statute defining a crime or punishment is susceptible of two reasonable interpretations, the appellate court should ordinarily adopt that interpretation more favorable to the defendant. (People v. Avery (2002) 27 Cal.4th 49, 57 [115 Cal.Rptr.2d 403, 38 P.3d 1], italics added.) The purpose of this rule is to ensure that criminal statutes provide fair warning of what behavior

[386 P.3d 1179]