The primary judicial branch of the International Union, the Court of International Justice’s main functions are to settle legal disputes submitted to it by states and to provide advisory opinions on legal questions submitted to it by duly authorized international branches, agencies, and the IU General Assembly. All IU members are automatically parties to the Court's statute, though non-IU members may also become parties to the Court's statute upon request (doing so will not, however, provide automatic jurisdiction over disputes involving said parties).
The Court of International Justice has 3 judges, each of different nationalities. In cases which a judge’s home nation is involved, they will typically excuse themselves from said case. In any contentious case, a party may make the request of a Ad hoc judge (to select one additional person to sit as a judge on that case only, though rather than them playing both a role in presenting/defending against the case and judging it they would choose an ally or trusted nation not already sitting as a judge).
There are two types of CIJ cases, contentious issues and advisory opinions.
In contentious cases (adversarial proceedings seeking to settle a dispute), the Court produces a binding ruling between states that agree to submit to the ruling of the court. Only states may be parties in contentious cases. Individuals, corporations, parts of a federal state, NGOs, IU organs and self-determination groups are excluded from direct participation in cases, although the Court may receive information from public international organizations and this does not preclude non-state interests from being the subject of proceedings if one state brings the case against another. For example, a state may, in case of "diplomatic protection", bring a case on behalf of one of its nationals or corporations.
An advisory opinion is a function of the Court open only to specified International Union bodies and agencies. On receiving a request, the Court decides which States and organizations might provide useful information and gives them an opportunity to present written or oral statements. Advisory Opinions are intended as a means by which IU agencies can seek the Court's help in deciding complex legal issues that might fall under their respective mandates (in other words if one wishes to question the powers and limits of the IU this would be the place).
The Court may turn to the Security Council for enforcement should it’s binding rulings on contentious cases not be observed by involved parties.
Edit: Judges would remain in their positions for 5 RP years