It is not the traditional stuff of nightmares. But you could forgive Boris Johnson and Rishi Sunak if their dreams this Christmas are haunted by a mellifluously voiced man in a double-breasted suit asking polite questions that are nonetheless extremely hard to answer. Hugo Keith KC is no stranger to prominence in the legal world, but as lead counsel to the Covid inquiry, his dogged quizzing of leading politicians, officials and scientists has brought him a national profile. During the inquiry’s just-ended second module, which covered decision-making at the heart of government, Keith tackled not only Johnson and Sunak, but the likes of Dominic Cummings, Michael Gove, Matt Hancock, Chris Whitty and Patrick Vallance. Keith’s role is fundamentally one of fact-finding – trying to uncover information that might help Heather Hallett, the inquiry’s chair, understand what happened and thus what, if any, lessons can be learned. There is, however, a necessarily adversarial element to this, particularly with the most recent hearings, as Keith questioned people with a very personal stake in the eventual findings on inconsistencies and omissions in their evidence. Some witnesses reacted with irritation, as when Johnson barked that descriptions of him saying older people could perhaps just accept their fate with the virus were “rubbish”. In contrast, Sunak coped by apparently forgetting almost everything from the pandemic period. As with all good barristers, Keith has shown a keen sense of when to ambush people with new evidence, such as screenshots of scurrilous WhatsApp exchanges or extracts from the diary of Vallance, the former chief scientific adviser. He has also had some fun, for example repeatedly stressing to the clear exasperation of Hancock that the former health secretary’s “pandemic diary” was not actually a diary, but written subsequently. Arguably the one witness to beat Keith at his own game was Gove, whose eloquent but meandering and frequently off-piste contributions prompted an irritable plea to please answer the questions rather than provide “a lecture”. However stellar this cast list, mastery of an inquiry room is standard practice for Keith, the 56-year-old joint head of chambers at the Three Raymond Buildings barristers’ practice, who appeared in the Leveson inquiry on behalf of Rebekah Brooks, the former Sun editor. Keith, who began as a barrister in 1989 and became a QC, as it was then, in 2009, is also well known to Hallett. He was counsel to the inquest into the 7 July 2005 terror attacks in London, over which she presided. Nor is rubbing legal shoulders with prominent people entirely new. In 2002, he represented Princess Anne when she became the first senior royal to be convicted of a criminal offence, having lost control of her dog. Anne pleaded guilty, with Keith’s job being to insist to the court in canine mitigation that her English bull terrier, Dotty, was “exceptionally good and wholly lacking in malice” and had merely “nipped” two children as a show of exuberance. The Covid inquiry is not a trial, even though witnesses also appear under oath. Similarly, Keith’s job is not to guide anyone towards a particular decision, just to generate as much clarity as possible for Hallett and her team. Some of his questions nonetheless contain the gravity and significance of the most serious criminal cases. One moment came with Johnson, when Keith noted that the former PM had apologised for errors during Covid: were these errors knowable only in retrospect, or could they have been avoided? Several minutes and some obfuscation later, an answer emerged: the former. It is up to Hallett if she agrees. But Johnson, Sunak, and all the others will wait anxiously for her opinion – and know that Keith very much helped to shape it.