Boris Johnson and Partygate: how did PM get only one fine?

Experts say it defies logic but Johnson attended gatherings deemed to have breached the rules without himself being fined

With the dust settling on the Metropolitan police's long investigation into Covid breaches inside Downing Street, one big question remains: how did Boris Johnson escape with just one fine?

Legal experts say it defies logic - and to many voters, it defies common sense too.