Where to start with your research of U.S. primary law?

Case law: you will most likely be researching asylum cases including Board of Immigration Appeals (BIA) agency decisions issued out of the Department of Justice, as well as federal circuit court cases.

Enacted law: You'll most likely be researching federal enacted law codified in the United States Code (U.S.C.) . A good deal of federal enacted law pertaining to immigration law including refugee law is contained in the Immigration and Nationality Act (INA), located within the U.S.C.   The INA is codified at Title 8, U.S.C., Aliens and Nationality, §§ 1101-1178.  Other code sections are located at different places throughout the U.S. Code, e.g., in Title 18 (Crimes and Criminal Procedure), and Title 22 (Foreign Relations).