The Forbes Commission spends twelve days in Haiti and reports

The commission Hoover sent reached Haiti on 28 February 1930 and reported on 26 March, having stayed only twelve days. Its members were W. Cameron Forbes as chairman, the diplomat Henry Fletcher, the Catholic layman Elie Vezina, and the editors James Kerney and William Allen White. Nearly all the witnesses at its hearings were presented by a committee of anti-Borno groups, and their denunciations, some exaggerated, drew heavy American press coverage. The report praised the record under Borno and General Russell but criticised them for not doing more to train Haitians for the responsibilities they would carry once the treaty expired. It recommended replacing the high commissioner with a civilian minister who would nationalise the treaty services, and it declined to propose abrogating the treaty or withdrawing the marines, saying it was under no illusions about what might follow.

The Fordney McCumber Act of 1922 had already set American import duties at prohibitive levels, and both parties promised more in 1928. Hoover wanted higher duties on farm imports and a tariff commission with power to adjust rates by half, which he thought would take the tariff out of congressional bargaining. What Congress produced was the Hawley Smoot Tariff of 1930, raising duties to the highest levels in American history. One thousand economists signed a petition asking for a veto. Thomas Lamont of J. P. Morgan said he had almost gone down on his knees to beg the president to reject it, and that the act sharpened nationalism everywhere. Hoover signed it in June 1930. Walter Lippmann wrote that the president had surrendered everything and got nothing. For countries that lived by selling coffee, sugar and other commodities into the American market, the door had just narrowed.

Herskovits found a Dahomean who made charms for a living and who came back to him repeatedly through 1931 with new ones. For each he explained how it had been made, what had gone into it and why, the taboos attached to it, who could use it, under what conditions and to what end. Charms meant to harm were included alongside charms meant to protect. The collection reached just under forty gbo with the details recorded for every one. A gbo could be worn at the waist, neck, wrist or ankle, kept inside a house, set at the edge of a field, buried in ground a man owned, worked into cuts in his skin, or swallowed. Once a specialist had sold a client the method, the right to make that charm belonged to the buyer as much as to the seller. A Dahomean proverb says the charm holds nothing for long, while the powers of the Vodu are eternal.

In December 1929 more than fifteen hundred Haitians marched on the southern port of Les Cayes carrying stones and clubs, in protest at what the world depression had done to a country that lived on coffee. Twenty United States marines held the town. They fired into the crowd and killed twelve people. Every element of the scene had been rehearsed in the Caribbean for four centuries: armed white men, unarmed black people, and a complaint about hunger treated as a public order problem. What made this repetition different was the audience. Washington now had to explain the deaths to American newspapers, and President Hoover authorised the Forbes Commission to examine the military occupation. It reached Haiti in February 1930 and recommended that Louis Borno hand power to a provisional government. Fourteen years of petitions, delegations to Congress and Senate testimony had moved the United States nowhere. Twelve bodies on a road outside Les Cayes started the machinery of withdrawal.