What is the test for determining whether a motion to dismiss or grant a mistrial is moot?

The jury was unable to reach a verdict on counts one and two and the court granted a mistrial and granted the prosecution's motion to dismiss. As a general rule, we decide only actual controversies. We do not render an opinion on moot questions or abstract propositions, nor do we declare principles or rules of law which cannot affect the matter before us. An issue becomes moot when a ruling can have no practical effect or provide a party with any relief. (People v. Rish (2008) 163 Cal.App.4th 1370, 1380.) We may consider an issue otherwise considered moot if it involves an important public interest that will otherwise evade review. (People v. Gregerson (2011) 202 Cal.App.4th 306, 321.)