What does Dominic Cummings do and why is he so important to Boris Johnson?

Cummings-gate has rocked the political world, dominating headlines and leading to calls for the prime minister's senior political advisor to resign.

Boris Johnson's adviser is being accused of contravening lockdown rules by making a 260-mile trip from London to his parent's house in Durham whilst experiencing Covid-19 symptoms. He's also admitted driving around 40 miles once he got there, though he denies that this or the initial trip was against the rules.

Boris Johnson maintains that Cummings behaved "responsibly, legally and with integrity". Cummings has also defended his actions in a Number 10 press conference, in which he refused to apologise.

But who is Dominic Cummings and what exactly does he do in government? Could they survive without him?

Cummings has been Johnson's senior political advisor since July 2019. It is his job to advise the prime minister on strategy, but he is not an elected member of the government like a cabinet minister or MP.

In fact, Cummings has never officially claimed to be a member of any political party, and has described his views as "not Tory, libertarian, populist or anything else".

Before Cummings-gate, he was best known first as a special advisor to Michael Gove, then as an architect of the Vote Leave campaign.

Some have suggested that the widespread outrage at Cummings is motivated by anger over Brexit.

Cummings co-founded the Vote Leave campaign in 2015, which went on to become the official campaign for leaving the European Union. He is credited with creating the slogan "take back control". Of course, the campaign wasn't solely responsible for bringing about Brexit and Cummings left the board almost four months before the vote, but it was certainly influential.

In March 2019, the House of Commons committee of privileges ruled that Cummings had been in contempt of parliament after failing to appear before MPs who were investigating fake news during the EU campaign.

Cummings was played by Benedict Cumberbatch in the Channel 4 drama Brexit: The Uncivil War.

Throughout the coronavirus pandemic, Boris Johnson has been advised by his Chief Medical Officer Chris Whitty and Chief Scientific Advisor Patrick Vallance, as well as by the other scientists and academics who make up the Scientific Advisory Group on Emergencies (SAGE). Cummings has, however, continued to play a major role in advising the prime minister.

In fact, Cummings was one of only 23 people to attend a SAGE meeting on 23 March, the day the UK officially went into lockdown. His presence at the meeting was criticised by those who pointed out that SAGE is supposed to be politically neutral. Downing Street responded by saying that he only ever attended SAGE meetings to listen in.

The government also defended Cummings against accusations that he was an early advocate of herd immunity, the idea that if enough people in a population are infected with a virus and built up resistance to it, the whole group will largely be protected. At least one cabinet minister has told reporters that Cummings was indeed an early advocate of herd immunity, but during his statement at Downing Street he suggested this isn't the case.

Cummings has also previously expressed scepticism at the efficacy of the Cabinet Office Briefing Rooms, or COBRA, meetings, writing that they result in "constant confusion between policy, politics and PR".

In short, the extent to which Cummings has guided the prime minister's strategy and communications throughout the pandemic isn't known. He has been tied inconclusively to the "stay at home" messaging campaign, for instance. But what is clear, is that when Boris Johnson makes a decision, Dominic Cummings is never far away.

Throughout Boris Johnson's premiership, Cummings's power has come under scrutiny. A man who can stroll in and out of Downing Street in a casual t-shirt and tracksuit is clearly a man to be reckoned with.

Cummings-gate has once again shone a light on how much influence Cummings has over Johnson, particularly given the prime minister's apparent reluctance to let him go.

Cummings spearheaded the Vote Leave campaign and was by the prime minister's side as he won an 80-seat majority in the 2019 general election, having stood on a pro-Brexit platform. Johnson was then plunged into the midst of one of the worst health crises the world has ever seen.

Working alongside an advisor who coached him to success must have been comforting to Johnson at the very least.

How the current government would fare without Dominic Cummings as de facto chief of staff is, of course, unknown, as the extent of his influence is not transparent.

But clearly, Boris Johnson wants to hang on to him and will go to extraordinary lengths to defend him. It is even unusual for an unelected advisor to address the public directly as he has done today in Number 10's rose garden.