Can the tax treaty apply to a US permanent resident working in US as a foreign government employee?

In a legal advice, the IRS Office of Chief Counsel has concluded that compensation paid to a U.S. permanent resident employed by a foreign government is not exempt from tax under the Belgium-U.S. income tax treaty.

The facts provide that a taxpayer lives and works in the U.S. as an employee of Belgium. The taxpayer, although not a U.S. citizen, is a lawful permanent resident (i.e. a green card holder).

In general, U.S. income tax treaties contain a “savings clause” that provides that a treaty will not affect the taxation by the U.S. of its residents and citizens (see e.g. Article 1(4) of U.S. Model  Income Tax treaty.) An exception to the savings clause is provided for in almost all income tax treaties, but it is not extended to persons who are permanent residents or citizens of the U.S. (permanent residents are treated as U.S. residents under Code Sec.  7701(b)(1)(A)(i)).

The memo notes that Rev Ruling 75-425 has given rise to some confusion with respect to employees of Belgium as it provided that income under the 1948 Belgium-U.S. income tax treaty exempted from tax  the compensation paid to employees who were citizens of the employing country. Prior to the publication of the ruling, however, the new 1970 income tax treaty between both countries was signed and did  not exempt such income from taxation. Rev Rul 75-425 was not updated, but was subsequently obsoleted by Rev Ruling 2007-60.