The Office of the Special Prosecutor (OSP) says it worked “behind the scenes” with the United States Federal Bureau of Investigation (FBI) to help secure the conviction of former Goldman Sachs banker and Tema Oil Refinery managing director Asante Kwaku Berko.
A federal jury in Brooklyn, New York, found Berko guilty on 6 August 2026 of conspiring to pay, and paying, more than $1m (£750,000) in bribes to several Ghanaian officials between 2014 and 2015.
The payments were linked to the development and financing of a power plant in Ghana under an agreement involving the Ghanaian government, Turkish energy company Aksa Enerji Uretim A.S. and Goldman Sachs, which was advising Aksa.
In a public notice issued on Monday, 10 August, the OSP said it had provided investigative and evidentiary support to the FBI through Ghana’s established mutual legal assistance framework.
The office said the United States Department of Justice had acknowledged its contribution as providing “significant assistance to this prosecution”.
Berko, a dual citizen of Ghana and the United States, faces a maximum sentence of 30 years in prison. He has been remanded pending sentencing, which is scheduled for 10 November 2026.
The OSP said the case demonstrated the importance of international co-operation in tackling corruption that crosses national borders.
It added that the work between the FBI and OSP had taken place behind the scenes, with the successful prosecution showing “the importance of mutual legal assistance.”
The Deputy Attorney-General, Dr Justice Srem Sai, has already said the Attorney General is working with United States authorities to pursue Ghanaian officials allegedly connected to the bribery scheme.
The alleged corruption relates to a power plant development contract agreed between the Ghanaian government and Aksa during the period from 2014 to 2017. Justice Srem Sai wrote about the matter on X.
What the jury heard
Berko went on trial in late July 2026 after prosecutors accused him of bribing Ghanaian government officials to help secure the power plant contract for Aksa.
Prosecutor Katherine Raut told the Brooklyn jury in her opening statement that Berko, 52, and associates outside Goldman Sachs had allegedly paid more than $1m to high-ranking Ghanaian officials a decade earlier. The payments were intended to secure approval for the development and financing of a multimillion-dollar power plant.
The jury convicted Berko on all counts in the indictment: conspiracy to violate the Foreign Corrupt Practices Act, violating the Act and conspiracy to commit money laundering. The verdict followed a nine-day trial before United States District Judge Diane Gujarati.
At the time of the deal, Berko was an executive director in Goldman Sachs’ Investment Banking Division. From December 2014, he was responsible for securing and managing the agreement between Ghana and Aksa, a Turkish energy company and Goldman Sachs client, to construct and finance the plant during a national energy crisis.
Prosecutors said Berko and his co-conspirators made, or agreed to make, payments to people at several levels of the Ghanaian government to ensure Aksa won the contract to build and operate the facility.
In April 2015, they discussed paying $1m to Ghana’s Minister of Power, who was responsible for securing important approvals for the project, and $250,000 to the minister’s senior adviser.
Five Ghanaian officials also allegedly received bribes during an all-expenses-paid trip to Turkey to inspect equipment intended for the plant.
After Ghana’s Parliament ratified the agreement in July 2015, Berko and his associates exchanged detailed emails about the payments. In August that year, they discussed $250,000 in bribes for various people, including $46,000 for members of Parliament who had ratified the deal. Prosecutors said Berko himself paid the parliamentary members.
During the same month, the conspirators referred to one recipient waiting for the “holy rain” meaning a bribe and said that person “would appreciate it sooner rather than later.”
Berko allegedly attempted to hide the arrangement from Goldman Sachs by misleading the company’s compliance team, which was responsible for reviewing the transaction. He also used a personal email address rather than his Goldman Sachs business account to discuss the agreement and payments, and instructed associates to do the same.
The payments were concealed and laundered through shell companies, sham invoices, nominee account holders and cash withdrawals. Money connected to the scheme moved through bank accounts in the United States and other countries.
Goldman Sachs eventually withdrew from the transaction because of corruption concerns.
The conviction was announced by Joseph Nocella Jr, United States Attorney for the Eastern District of New York; A. Tysen Duva, Assistant Attorney General in the Justice Department’s Criminal Division; and James C. Barnacle Jr, Assistant Director in Charge of the FBI’s New York Field Office.
“Today’s verdict marks another significant victory in this Office’s longstanding commitment to rooting out corruption,” stated United States Attorney Nocella.
“The defendant abused his access to high-level foreign government officials and his platform as an investment banker at a prestigious American firm to line his own pockets with millions of dollars,” it added.
“We live in a global economy that American companies must be able to compete in fairly,” said Assistant Attorney General Duva of the Justice Department’s Criminal Division.
“This defendant corrupted that fair competition. He abused his position at a world-renowned American investment bank by helping bribe Ghanaian officials, so he and his co-conspirators, including senior executives at a Turkish company, could make money. Today’s conviction makes clear that criminals who undermine our country’s interests by corrupting foreign governments and cutting off fair competition will face the full force of the Department of Justice.”
“Today’s verdict highlights the importance of domestic and international partnerships, and the magnitude of success that working together creates. The FBI is thankful for the assistance from the Department of Justice and the United Kingdom – specifically to the Office of International Affairs, U.S. Marshals Service, and INTERPOL – in pursuing justice to protect our country’s financial integrity,” stated FBI Assistant Director in Charge Barnacle.
Nocella also thanked the UK government, the UK National Centre Bureau for INTERPOL, the United States Embassy in London, the Justice Department’s Office of International Affairs and the United States Marshals Service for their substantial assistance in securing Berko’s arrest and extradition.
The case is being prosecuted by the Business and Securities Fraud Section of the United States Attorney’s Office for the Eastern District of New York and the Criminal Division’s Fraud Section. Assistant United States Attorneys Jessica Weigel, Nick M. Axelrod and Tara McGrath are prosecuting alongside Assistant Chief Katherine Raut and Senior Trial Attorney Katherine Nielsen, with support from paralegal specialists Melina Piatti-Chayan, Isha Jayadev and Teresa Dolan.
