Former Nigerian Petroleum Minister Diezani Alison-Madueke has accused UK authorities of damaging her reputation and personal life following a lengthy corruption investigation that ended with her acquittal on all bribery charges.
Speaking exclusively to the BBC after being cleared by a London court, Alison-Madueke described the 13-year investigation by the UK’s National Crime Agency (NCA) as “painful and traumatic,” saying the case had severely restricted her freedom and career opportunities.
“I’ve not been allowed to travel. I’ve not been allowed to work. They destroyed my reputation and my integrity,” she said.
The 65-year-old was found not guilty on Wednesday at Southwark Crown Court of five counts of accepting bribes and conspiracy to commit bribery following a trial that began in January.
Alison-Madueke, who served as Nigeria’s petroleum minister from 2010 to 2015, also made history as the first woman to lead the Organization of the Petroleum Exporting Countries (OPEC).
Reflecting on the impact of the investigation, she said the experience had taken a significant psychological toll.
“When your freedom is taken away from you, it has a very deep impact on you psychologically,” she said. “I knew that I had never done anything wrong and that I had not committed any of the offences I was being accused of.”
The former minister was first arrested in 2015 but was not formally charged until 2023. Prosecutors alleged that she accepted lavish benefits from wealthy oil businessmen who held government contracts, including luxury purchases worth approximately £2 million from Harrods, chauffeur-driven vehicles and access to high-value properties in London and Buckinghamshire.
Throughout the trial, defence lawyers challenged the prosecution’s case, arguing that key documents that could have supported Alison-Madueke’s defence had disappeared in Nigeria.
According to her, the missing records included receipts which she said showed that payments made on her behalf by oil executives had later been reimbursed.
She claimed the documents were seized from her residence in Abuja by Nigerian intelligence officials in 2015 and said she has no knowledge of their whereabouts.
Former Nigerian President Goodluck Jonathan, under whom Alison-Madueke served, also provided a statement to the court indicating that it was common for third parties to cover transportation and accommodation costs for ministers undertaking official overseas assignments.
Asked who should bear responsibility for the shortcomings in the case, Alison-Madueke said both Nigerian and British authorities should reflect on how such investigations are conducted.
“There’s a bit of blame everywhere,” she said. “The Nigerian authorities need to review the processes and practices they deploy in these types of cases.”
She also suggested that international law enforcement agencies should exercise greater caution when handling politically sensitive investigations abroad.
“The long arm of the law, when operating in other countries, particularly in politically motivated cases, needs to show much greater sensitivity,” she said.
Alison-Madueke argued that investigators overlooked the reforms she said she introduced to combat corruption within Nigeria’s oil sector and failed to appreciate the political challenges she faced.
“I was the first woman to hold the position of petroleum minister and later become head of OPEC in what remains a largely male-dominated environment,” she said.
In response, the NCA said it had conducted a thorough and complex investigation that was regularly reviewed by the Crown Prosecution Service (CPS) throughout its duration.
The agency said investigators worked closely with international partners and carried out the inquiry impartially before submitting evidence to prosecutors, who approved the charges.
“We respect the decision of the jury,” an NCA spokesperson said.
Alison-Madueke’s brother, Archbishop Doye Agamas, 69, was also acquitted of conspiracy to commit bribery. Oil industry executive Olatimbo Ayinde, 54, was similarly cleared of all charges, including bribery and bribery of a foreign public official.
Despite her acquittal in the UK, questions remain over other investigations linked to her tenure in office.
In 2023, the United States Department of Justice announced the recovery of assets worth $53 million that had been seized from two oil businessmen named during the trial. US authorities alleged at the time that Alison-Madueke had used her influence to direct lucrative oil contracts to companies connected to the men.
Responding to those allegations, Alison-Madueke said she had never been given an opportunity to challenge the claims because she was never charged in the matter.
“I was never given the opportunity to fight that because I wasn’t even charged,” she said, insisting that the contracts followed the required approval processes.
Nigeria’s anti-corruption agency, the Economic and Financial Crimes Commission (EFCC), has also previously announced the recovery of approximately $153 million and more than 80 properties linked to investigations involving the former minister.
Addressing those claims, Alison-Madueke maintained that the forfeited assets had not been directly traced to her and said she intends to examine the details now that the UK proceedings have concluded.
“I don’t know exactly what has happened in those matters. Now that I have my freedom, I will be able to find out what has gone on,” she said.