An obscure clause in the Constitution could pose problems for President-elect Donald Trump.
The "Emoluments Clause," which effectively bars federal officials from doing business with or taking gifts from foreign governments without congressional approval, has come to the forefront due to Trump's sprawling business interests around the globe. A former chief White House ethics lawyer for President George W. Bush told ThinkProgress that Trump has already shown some behaviors that could test the rule.
Here's the clause in question from Article I, Section 9 of the Constitution:
No Title of Nobility shall be granted by the United States: And no Person holding any Office of Profit or Trust under them, shall, without the Consent of the Congress, accept of any present, Emolument, Office, or Title, of any kind whatever, from any King, Prince, or foreign State.