No 10 advisers at Sage meetings: key questions that need answering

How and why Ben Warner and Dominic Cummings contributed to Covid-19 meetings is unclear

• Sage attendees worried by Cummings' presence
• No evidence No 10 advisers attended Sage in previous crises
• See all our coronavirus coverage

The government has not disputed that this is the first time Downing Street political advisers have attended Sage meetings and asked questions at them. No 10 argues that the unprecedented scale of the coronavirus pandemic made it necessary. However, the government's policies say scientific committees such as Sage should be politically neutral. Sage meetings are chaired by the government's chief scientific adviser, Sir Patrick Vallance. However, a government spokesperson said Vallance "would not have to sign off" on observers or representatives from government departments. So who decided they should attend, and why and when was the decision made?