Foreign, Comparative and International Legal Research

Public international law governs the relationships between the national governments of different nations,  intergovernmental organizations of different nations, and relationships spanning between national governments and foreign intergovernmental organizations. Issues addressed by public international law include human rights, international trade, and intellectual property.

Public International Law would govern the following:

• Tariffs on a particular type of imported goods
• Investigations and sanctions pertaining to war crimes
• Whether a trademark in country A is enforceable in country B

In contrast, private international law governs the choice of law when there are conflicts in the domestic law of different countries as they relate to private transactions between parties from different nations. Common topics include contracts and family law.

Private International Law would govern the following:

• A divorce between people in different countries
• The contracts pertaining to a business in country A's acquisition of a country B corporation

Source; International Legal Research in a Nutshell, Hoffman (2021)

Comparative law is not a type of law, but the study of the similarities and differences between legal systems of different nations. It often helps legal scholars understand the history and aims of law within their own jurisdiction, and as a practical matter, may provide insight on both domestic and international client matters.

"Foreign" law simply refers to the law of foreign nations. From the perspective of U.S. law, foreign law may be necessary to study public and private international law as well as draw comparisons between jurisdictions.