Fullbrook was working as a political consultant when he provided research in 2020 on Julio Herrera Velutini, a Venezuelan-Italian banker accused of bribing the governor of Puerto Rico during the same period. A senior organizer in Conservative party politics for decades, who was appointed chief of staff to No 10 after Liz Truss campaigned for the Tory leadership, Fullbrook said he had broken no law and was unaware that his then-client might have had corrupt incentives to hire him as a consultant. According to the US indictment, Herrera Velutini offered to contribute to Wanda Vázquez Garced’s campaign for re-election as governor of Puerto Rico in exchange for Vazquez Garced firing the island’s financial regulator, which was investigating Herrera Velutini’s bank. Herrera Velutini is alleged to have offered $300,000 in support. The start of the process in the US caused controversy in the UK because Britannia Financial Services, a company founded and largely owned by Herrera Velutini, has given more than £500,000 to the Conservative party since 2019. Labor said that, under light The allegations against the banker, the Tories will have to give the money back. Herrera Velutini denies wrongdoing and contests the charges against him, which carry a total maximum sentence of 20 years in prison. Fullbrook is involved because at the time he worked for CT, a political consultancy founded by Sir Lynton Crosby, who has run general election campaigns for many Tory leaders. Herrera Velutini was paying CT for consulting services that could help Vazquez Garced in her re-election. According to a report in the Sunday Times, Fullbrook was the lead consultant on the project and flew to Puerto Rico in February 2020, six months before the election. The company conducted an opinion survey related to the campaign. Vazquez Garced did fire the financial regulator in February 2020, but lost her re-election campaign anyway in August of that year. According to the Justice Department’s indictment, Herrera Velutini then tried to bribe her successor by offering financing in exchange for a favorable audit of his bank. According to the Sunday Times, the FBI approached the National Crime Agency and the Metropolitan police in April this year to secure Fullbrook’s attendance for an official interview. Fulbrook is being treated as a witness in the case. A Fullbook spokesman said it obeyed the law in all the countries it worked in and was confident it had done so in this case. The spokesperson continued: “Indeed, Mark Fullbrook is a witness in this matter and has fully, completely and voluntarily cooperated with the US authorities in this matter, as he always would in any circumstance where his assistance is requested by the authorities.” According to the spokesperson, Fullbrook was unaware of Herrera Velutini’s alleged intent to bribe the governor when CT was working for him, and Fullbrook only learned of this allegation in April 2022. The representative also said that while Fullbook met Vazquez Garced, it never produced work for her. The opinion poll conducted by the company was provided to Herrera Velutini, the spokesman said. As the US Department of Justice revealed in August, two people – a banker and a political consultant from Puerto Rico – have already pleaded guilty to conspiring with Herrera Velutini to bribe a public official. At the time, the US attorney for Puerto Rico, William Steven Multrow, said: “The criminal actions of the defendants in this case strike at the heart of our democracy and further erode our citizens’ trust in their institutions of government.” Downing Street declined to comment on the story.