The court examined the Spanish Universal Jurisdiction Law and held that article 23.4 of the Spanish Organic Judiciary Act (which establishes Spanish universal jurisdiction) appears to create an absolute universal jurisdiction rule, which can only be restricted by the principle of ne bis in idem (double jeopardy). However, it had already been decided by Spanish Supreme Court jurisprudence that there are some other restrictions to this principle.[3] These restrictions include, inter alia, the principle of locus delicti, which gives priority to the state in whose territory the actions in question took place. Moreover, it was repeatedly stated by the Spanish Supreme Court that the requirement of some link or connection between the criminal acts and some interest or value to the citizens exercising universal jurisdiction might constitute reasonable criterion of self-restriction that would prevent misuse of the law. Such linkage or interest would help to ensure the effectiveness of intervention by the courts. The Court emphasized that this connection has to be genuine or substantial in order to be compatible with the principles of nonintervention in the affairs of other states and proportionality.
Another restriction relates to the authority of territorial jurisdiction to effectively prosecute actions committed in a foreign state.The Court of Appeals mentioned in this regard previous rulings, which concluded that it is both logical and suitable to establish rules of priority between jurisdictions. In order to resolve jurisdictional conflicts, it is necessary to establish the precedence of the state in which the acts were committed except when the state demonstrates an unwillingness or inability to prosecute the allegedly criminal acts. This principle is particularly relevant when there are ongoing proceedings related to the same case in a state that has a stronger judicial connection.
Applying these criteria to the Shehadeh case, the Court of Appeals held that Spain could not implement universal jurisdiction since the Israeli local judicial system has priority over Spanish universal jurisdiction. The Court of Appeals agreed with the prosecutors' claim that the investigation that is under way in Israel, pursuant to the rulings of the Israeli High Court of Justice in the targeted killing case[4] and in the Shehadeh Case,[5] is a genuine and legitimate course of action by the Israeli government and the Israeli judicial system. The Court emphasized the fact that the conclusions and decision of the investigation team are subject to review by the Israeli Supreme Court.
Therefore, based on the existence of a genuine ongoing investigation in Israel and the stronger territorial jurisdiction of the Israeli judicial system, the Court held that there is no need for a Spanish inquiry of the matter.
The Dissenting Opinion - The dissenting opinion of four justices on the Court claimed that the decision of the majority in this case would result in impunity and the denial of Spanish Universal Jurisdiction Law. According to the dissenting opinion, there is a hierarchy of the severity of the crimes that fall within article 23.4 of the Organic Judiciary Act. According to this hierarchy, the crime of genocide and war crimes are considered to be "first degree crimes," while crimes of terrorism and drug-trafficking are deemed to be of a lesser degree. The crime that is being questioned in this case is of the first degree and includes excessive attacks against innocent civilians with the aim of terrorizing them.
The dissenting opinion noted that Israel, which has a “permissive” court and conducts targeted killings under the pretext of maintaining a legitimate war on terrorism," caused the death of numerous innocent civilians. This approach prevents Israel from conducting genuine investigations and punishing such actions.
The dissenting opinion stressed that the Spanish Constitutional Court had already determined that Spanish universal jurisdiction is absolute and that subsidiarity cannot serve as a limitation. Moreover, the duty to prosecute under international law is not based on territory – an observation that is particularly germane to the Shehadeh targeted killing operation, which occurred in Gaza under the Palestinian Authority's judiciary authority. Moreover, the Spanish Court’s investigation cannot be viewed as intervention in the internal affairs of the State of Israel because violations of international law are not considered the internal affairs of a state.
According to the minority opinion, the only restriction of Spanish universal jurisdiction is the existence of an ongoing investigation or the ne bis in idem principle. However, the current Israeli administrative inquiry falls short of complying with the requirements of effective investigation. According to the Israeli military, the findings of an internal field investigation cannot serve as the basis for a criminal investigation. With regard to the investigation committee, it is still unclear whether or not the committee will recommend criminal proceedings of any kind. Therefore, the majority's decision to dismiss the inquiry due to the existence of an ongoing criminal investigation, prior to the beginning of actual criminal proceedings, is groundless.