The two lobbyists, who are accused of passing U.S. secrets to an Israeli official, argue that Rice and others can verify their claim that the United States regularly uses the American Israel Public Affairs Committee to send back-channel communications to Israel.

Lobbyists Steven Rosen and Keith Weissman subpoenaed Rice, National Security Adviser Stephen Hadley, Deputy National Security Adviser Elliott Abrams and a dozen others to testify.

Federal prosecutors unsuccessfully challenged the subpoenas. If the officials ultimately testify, the trial in federal court in suburban Alexandria, Va. could offer a behind-the-scenes look at the way U.S. foreign policy is crafted.

The lobbyists are accused of receiving classified information from a now-convicted Pentagon official and relaying it to an Israeli official and the press. The information included details about the al-Qaida terror network, U.S. policy in Iran and the bombing of the Khobar Towers dormitory in Saudi Arabia, federal prosecutors said.

But defense attorneys argued that top U.S. officials regularly used the lobbyists as a go-between as they crafted Middle East policy. If so, attorneys say, how are Rosen and Weissman supposed to know the same behavior that's expected of them on one day is criminal the next?

U.S. District Judge T.S. Ellis III said the lobbyists have a right to argue that "they believed the meetings charged in the indictment were simply further examples of the government's use of AIPAC as a diplomatic back channel."