A scientist who has been helping the government with the Covid-19 crisis has resigned from Sage - the Scientific Advisory Group for Emergencies.

Professor Neil Ferguson’s research aided Boris Johnson in his decision to impose the UK lockdown, but he said he regrets “undermining” the continued need for social distancing.

His admission came after it was claimed he broke the rules.

So what happened, and who are Sage? Here's all you need to know.

What is Sage?

Sage provides scientific and technical advice to support decision makers in the government during national emergencies.

The group is responsible for ensuring timely scientific advice is made available to support government decisions in the Cabinet Office Briefing Room (COBR).

Its membership is dependent on the nature of the emergency, but it typically includes leading experts from within the government, along with leading experts from the fields of academia and industry.

Who is on the committee?

Sage is usually chaired by the government’s chief scientific advisor, Sir Patrick Vallance.

He is responsible for providing scientific advice to the Prime Minister and members of the cabinet, advising on aspects of policy on science and technology, and improving the quality and use of scientific evidence in government.

These are the members of the Sage committee:

  • Sir Patrick Vallance FMedSci FRS - Government Chief Scientific Adviser
  • Professor Chris Whitty CB FMedSci - Chief Medical Officer and Chief Scientific Adviser,
  • Department of Health and Social Care
  • Professor John Aston - Chief Scientific Adviser, Home Office
  • Professor Wendy Barclay FMedSci - Imperial College London
  • Professor Phil Blythe - Chief Scientific Adviser, Department for Transport
  • Professor Dame Angela McLean FRS - Chief Scientific Adviser, Ministry of
  • Defence Professor Graham Medley - London School of Hygiene & Tropical Medicine
  • Professor Andrew Morris FMedSci FRSE - University of Edinburgh
  • Professor Carole Mundell - Chief Scientific Adviser, Foreign and Commonwealth Office
  • Professor Cath Noakes - University of Leeds
  • Dr Rob Orford - Welsh Government
  • Professor Michael Parker - University of Oxford
  • Professor Sharon Peacock FMedSci - Public Health England
  • Professor Alan Penn - Chief Scientific Adviser, Ministry of Housing, Communities and Local Government
  • Professor Steve Powis FRCP - National Health Service England
  • Dr Mike Prentice - National Health Service England
  • Mr Osama Rahman - Chief Scientific Adviser, Department for Education
  • Professor Venki Ramakrishnan PRS - Ex Officio as Chair of DELVE, convened by the Royal Society
  • Professor Andrew Rambaut FRSE - University of Edinburgh
  • Professor Tom Rodden - Chief Scientific Adviser, Department for Digital, Culture, Media and Sport
  • Professor Brooke Rogers OBE - Kings College London
  • Dr James Rubin - Kings College London
  • Professor Calum Semple - University of Liverpool
  • Dr Mike Short CBE - Chief Scientific Adviser, Department for International Trade
  • Dr Gregor Smith - Scottish Government Chief Medical Officer
  • Professor Sir David Spieglhalter FRS - University of Cambridge
  • Professor Jonathan Van Tam MBE - Deputy Chief Medical Officer
  • Professor Russell Viner PRCPCH - University College London
  • Professor Charlotte Watts CMG FMedSci - Chief Scientific Adviser, Department for International Development
  • Professor Mark Walport FRCP FMedSci - FRS UK Research and Innovation
  • Professor Mark Woolhouse FRSE - University of Edinburgh
  • Professor Lucy Yardley - University of Bristol
  • Professor Ian Young - Northern Ireland Executive
  • Professor Maria Zambon FMedSci - Public Health England

What rules did Professor Ferguson break?

Professor Ferguson reportedly allowed a woman, said to be his “lover”, to visit him at home in London on at least two occasions during the lockdown, despite his research warning that 250,000 people could die in the UK before the Prime Minister imposed the restrictions.

He said: “I accept I made an error of judgment and took the wrong course of action. I have therefore stepped back from my involvement in Sage

"I acted in the belief that I was immune, having tested positive for coronavirus, and completely isolated myself for almost two weeks after developing symptoms.

"I deeply regret any undermining of the clear messages around the continued need for social distancing to control this devastating epidemic.

“The Government guidance is unequivocal, and is there to protect all of us."