 In July 1866, Havemeyer was selected, along with Thurlow Weed, as arbitrator in the matter of a controversy relative to certain claims which had been pending for more than ten years between the Board of Public Charities and Correction and the Board of Commissioners of Emigration involving an amount of more than $100,000.The report was accepted as satisfactory by both parties, and the controversy settled.In the wake the Boss Tweed financial scandal, which forced the political boss of Tammany Hall to flee the country, Havemeyer was named vice president of the political reform organization Committee of 70 and assisted in organizing reform associations in all the city's assembly districts.