Speaking at the opening of a library at South Ruislip in north west London, Mr Johnson said people could not swear at police and expect to get away with it.
If I read the papers correctly there was a proposal to arrest Mr Mitchell for what he said. That seems to be wholly common-sensical.
The public order act does allow for police officers' discretion in this matter. They've obviously decided not to go ahead with it.
But it shows the gravity of this offence.
More top news
A total of 1.7 million attacks were carried out against more than 650,000 victims of which just over 52,000 were in the UK.
The men were using ropes to lever the sofa up to the first floor apartment because it was too large to fit through the doors.
He's not even halfway.