In July 1766 he was recalled to Paris to become secretary of the Council of State and chief clerk in the Bureau of Foreign Affairs.
[1] Early in 1778, under instructions from Vergennes, he conducted the negotiations with the American representatives, Benjamin Franklin, Silas Deane, and Arthur Lee, which resulted in the signing of the Treaty of Alliance and the Treaty of Amity and Commerce with the United States on February 6, 1778.
He sailed in company with Silas Deane aboard the comte d'Estaing's flagship of the seventeen-ship battle fleet transporting four thousand French troops.
Congress welcomed Gerard on July 14, one day before it opened investigations into charges against Deane.
His activity in America consisted chiefly in subsidizing writers — of whom Thomas Paine was the best known — to create a sentiment favorable to a closer French alliance, and in somewhat questionable relations with various members of Congress, who were the recipients of "gifts" from him.