Paula Dodds, Chair of the Metropolitan Police Federation, said: "This is very much the right decision that will not only be welcomed by the officer and his family - but all police officers across London.
"It is imperative that there are policies in place for operational policing which support lawful decisions made by officers, based on their training, so that they should not be placed in fear of the loss of their liberty and livelihood.
"Police officers are of course - and rightly - highly accountable for their actions. But the officer has sadly suffered years of legal scrutiny following this incident.
"We are pleased this has all now concluded and that the officer can continue to serve the public without this hanging over him.
"We thank his legal team for their years of hard work on this case."