International tax litigation in the U.S. relies on several legal sources and interpretive materials to help courts decide how tax laws, regulations, and treaties apply. These sources may include statutes, court decisions, Treasury Regulations, IRS guidance, tax treaties, and related materials. This may also include international documents such as the OECD Model Tax Convention and the Vienna Convention on the Law of Treaties.
U.S. Courts use these sources in both domestic and international tax disputes to resolve uncertainties, address interpretive gaps, and apply the law consistently. Court decisions set examples for future cases, while administrative and international guidance helps courts understand complex tax rules and treaty requirements.
In international tax disputes, courts often need to connect U.S. tax rules with international standards and agreements. By looking at both binding legal sources and helpful interpretive materials, courts apply tax laws and treaties to real-life situations.
Now, let’s look at the legal sources and interpretive guidance that U.S. courts use in domestic tax cases.