see - sc.judiciary.gov.ph/jurisprudence/2013/march2013/184658.pdf
"x x x.
Respondent judge committed grave
abuse of discretion in granting the
demurrer.
It has long been settled that the grant of a demurrer is tantamount to
an acquittal. An acquitted defendant is entitled to the right of repose as a
direct consequence of the finality of his acquittal.15 This rule, however, is
not without exception. The rule on double jeopardy is subject to the exercise of judicial review by way of the extraordinary writ of certiorari under Rule 65 of the Rules of Court. The Supreme Court is endowed with the power to determine whether or not there has been a grave abuse of discretion amounting to lack or excess of jurisdiction on the part of any branch or instrumentality of the government.16 Here, the party asking for the review must show the presence of a whimsical or capricious exercise of judgment equivalent to lack of jurisdiction; a patent and gross abuse of discretion amounting to an evasion of a positive duty or to a virtual refusal to perform a duty imposed by law or to act in contemplation of law; an exercise of power in an arbitrary and despotic manner by reason of passion and hostility; or a blatant abuse of authority to a point so grave and so severe as to deprive the court of its very power to dispense justice.17 In such an event, the accused cannot be considered to be at risk of double jeopardy.18
The trial court declared that the testimonies of PO2 Frando, PO2 Cubian, P S/Insp. Manaog, and AIDSOTF Chief Leonardo R. Suan were insufficient to prove the culmination of the illegal sale, or to show their personal knowledge of the offer to sell and the acceptance thereof. In granting the demurrer filed by the accused, respondent judge surmised that it was the CI who had initiated the negotiation of the sale and should have thus
been presented at trial.
x x x."
