The last time a Conservative government was in the midst of a crisis like partygate, Labour had a choice. Should it stick or twist? Should it passively allow Conservative voters, who had kept the party in power for more than decade, to drift away from John Major, thanks to his troubles over the economy, ‘sleaze’ and the EU, hoping they would remain with Labour come a general election? Or should it make a bold and positive case for why they could actively support Labour?

Both approaches held dangers.