Subpoena from 3M would force defence secretary Liam Fox to answer claim under oath in US court Liam Fox, the defence secretary, may be forced to give evidence in a blackmail trial in the United States, the Guardian has learnt. The “unprecedented” legal action could make Fox the first serving British cabinet minister to give evidence in a serious legal case in America. The Guardian understands that US conglomerate 3M is preparing to serve Fox with a subpoena demanding that he gives evidence over a claim that he was aware of a threat to interfere with the award of a knighthood to 3M’s British-born chief executive. It has been alleged that a private equity partner of the Ministry of Defence demanded that 3M hand over $30m (£18.5m) or risk the embarrassment of the government interfering with the knighthood award to George Buckley, 3M’s chief executive. It has been alleged that Fox was party to a conversation about the alleged suggestion. A 3M subpoena would force Fox to answer the claim under oath. An email to the private equity company from 3M’s lawyers, seen by the Guardian, said: “We request that you accept subpoenas on [Fox's] behalf for the production of documents and deposition upon oral testimony.” 3M’s lawyers have yet to serve a subpoena on Fox. Harvey Boulter, chief executive of Porton Capital, which worked with the government to develop innovative technology to help combat MRSA, has been accused of blackmail and served with legal papers. Boulter and Porton Capital deny the claim. According to 3M’s lawyers, Boulter told them that if an earlier legal battle over the MRSA technology was not settled out of court he would use his political influence to interfere with Buckley’s recently awarded knighthood. The blackmail case is built on emails Boulter sent to 3M’s lawyers last month. “As a result of my meeting [with Fox] you ought to understand that David Cameron’s cabinet might very shortly be discussing the rather embarrassing situation of George [Buckley]‘s knighthood. It was discussed today,” Boulter said in one of the emails. “Governments are big and sometimes decisions in one part are not well co-ordinated.” Bill Brewer, 3M’s lawyer, said: “We are committed to determine who aided, abetted or participated with Boulter in any manner relative to the demands that were made to 3M during the weekend of 18 June.” The MoD has denied that Fox discussed the continuing legal case or Buckley’s knighthood. However, in a new statement, Boulter has again claimed that he and Fox discussed the litigation. The MoD declined to issue a fresh statement. Mark Stephens, a high-profile media lawyer with London firm Finers Stephens Innocent, said: “Calling a serving British cabinet ministers to give evidence is pretty unprecedented.” Stephens said that if the subpoena is served Fox would be pushed to give evidence in America or speak to US lawyers in a British court. Private equity Liam Fox United States Defence policy Rupert Neate guardian.co.uk