Police authority retires 21 aigs

It seems like you're referring to a news article or a report about the police authority retiring 21 AIGs (Assistant Inspector-Generals). Can you please provide more context or details about the article or report you're referring to? This will help me better understand the situation and provide a more accurate response.

Additionally, I'd like to clarify that AIGs are typically high-ranking officers in a police force, and their retirement can have significant implications for the organization. It would be interesting to know more about the reasons behind their retirement, the impact on the police force, and any potential changes that may be implemented as a result.

Please feel free to share more information, and I'll do my best to provide a helpful response!