The Secret Barrister on Twitter has bought a bit of clarity on what the fines mean;
	Quote:
	
	
		| A Fixed Penalty Notice means that the police believe Johnson and Sunak to have broken the law. 
 It is not, of itself, a conclusive finding that they have.
 
 If they are not guilty, they can refuse to pay, and contest the charges in the magistrates’ court.
 
 Which might be fun.
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 Mind you, you can be pretty damn sure that the Police have got ironclad evidence to take the political risk of sending a penalty notice the the PM and Chancellor. Getting this wrong would be severely career limiting for some poor copper.