What's a normal pattern of rank in CID versus age and time in the police? What would be consider young for the rank? Eg, my 31/32-yo guy who's been in the police about 10 years, what would he be doing?
Modern-day. Large city, but not London (I assume that would make a difference?)
Googled: minimum age CID ranks, age detective ranks, combinations of age + names of various ranks