In 1975, Senators John Sparkman and George McGovern were accused of violating the Logan Act when they traveled to Cuba and met with officials there. In considering that case, the U.S. Department of State concluded:

The clear intent of this provision [Logan Act] is to prohibit unauthorized persons from intervening in disputes between the United States and foreign governments. Nothing in section 953 [Logan Act], however, would appear to restrict members of the Congress from engaging in discussions with foreign officials in pursuance of their legislative duties under the Constitution. In the case of Senators McGovern and Sparkman the executive branch, although it did not in any way encourage the Senators to go to Cuba , was fully informed of the nature and purpose of their visit, and had validated their passports for travel to that country.

Senator McGovern’s report of his discussions with Cuban officials states: "I made it clear that I had no authority to negotiate on behalf of the United States — that I had come to listen and learn...." (Cuban Realities: May 1975, 94th Cong., 1st Sess., August 1975). Senator Sparkman’s contacts with Cuban officials were conducted on a similar basis. The specific issues raised by the Senators (e.g., the Southern Airways case; Luis Tiant’s desire to have his parents visit the United States) would, in any event, appear to fall within the second paragraph of Section 953.

Accordingly, the Department does not consider the activities of Senators Sparkman and McGovern to be inconsistent with the stipulations of Section 953.[6]

He shall have power, by and with the advice and consent of the Senate, to make treaties, provided two thirds of the Senators present concur; and he shall nominate, and by and with the advice and consent of the Senate, shall appoint ambassadors, other public ministers and consuls, judges of the Supreme Court, and all other officers of the United States, whose appointments are not herein otherwise provided for, and which shall be established by law: but the Congress may by law vest the appointment of such inferior officers, as they think proper, in the President alone, in the courts of law, or in the heads of departments.

To regulate commerce with foreign nations, and among the several states, and with the Indian tribes;
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To define and punish piracies and felonies committed on the high seas, and offenses against the law of nations;

To declare war, grant letters of marque and reprisal, and make rules concerning captures on land and water;
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To make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the government of the United States, or in any department or officer thereof.