Steve Vick­ers, a for­mer head of the colo­nial police’s Crim­i­nal Intel­li­gence Bureau, left the force in 1993 ahead of the han­dover and has since set up a risk con­sul­tan­cy business.

He said expat offi­cers remain­ing after the han­dover were use­ful because ​“con­ti­nu­ity and con­fi­dence was maintained”.

“To that end, their pres­ence was valu­able, and indeed desir­able,” he told AFP.

But he added that Hong Kong’s police force has since changed con­sid­er­ably, espe­cial­ly as Bei­jing asserts more author­i­ty over the city’s leaders.

“As the years have gone by, and Chi­na’s rise has been much more pro­nounced, the Hong Kong gov­ern­ment became politi­cised in the years fol­low­ing the han­dover,” he said.

“This politi­ci­sa­tion also affects the police.”