Not always. International law and domestic law are separate systems. In many countries, international treaties must be incorporated into national law through legislation before they have direct effect. For example, a state may sign a treaty, but its provisions only take effect in local courts until parliament passes a law implementing them. Some states (like the Netherlands) give treaties direct effect, while others (like the UK) require an act of parliament. International law creates commitments between states, but whether individuals can rely on it in domestic courts depends on how each country’s legal system is set up..

No. The International Court of Justice (ICJ) settles disputes between states, such as border disagreements or treaty interpretations. It does not handle cases against individuals. That role belongs to courts like the International Criminal Court (ICC), which prosecutes individuals for the most serious international offences. . Confusing the ICJ and the ICC is common, but they serve different purposes within international law.

No. States are only bound by treaties they have signed and ratified. Membership in the United Nations does not automatically mean acceptance of all international agreements. For instance, while most UN members have joined the Geneva Conventions, some other treaties — such as the Rome Statute of the International Criminal Court — have fewer parties. Consent remains the foundation of treaty law.