Why is the Hong Kong police called the Royal Hong Kong Police?

Use the title before the return of Hong Kong. Before 1997, Hong Kong was a British colony. At that time, the name of the Hong Kong police was the Royal Hong Kong Police, so the title before the return of Hong Kong was used. Hong Kong, the full name of People's Republic of China (PRC) Special Administrative Region, is located in the south of China, east of the Pearl River Estuary, facing Macau across the sea in the west and adjacent to Shenzhen in the north.