Nicola Sturgeon has called on Boris Johnson to sack controversial Downing Street adviser Dominic Cummings for breaking lockdown.Scotland's First Minister spoke out after a furious backlash at Cummings for driving between London and Durham with family despite travel restrictions.Sturgeon said she had to lose her former top medical adviser, Dr Catherine Calderwood, when it emerged she'd twice visited a holiday home.On social media today, Sturgeon wrote: "I know it is tough to lose a trusted adviser at the height of crisis, but when it's a choice of that or integrity of vital public health advice, the latter must come first."That’s the judgment I and, to her credit, Catherine Calderwood reached.