I'm not a fan of story progression, but I love seeing my played cops interact with each other at the police station! There are three couples among them and one of those couples tends to make out in the evidence lab <3
I learnt this only late, but here's the "secret": The officers work shifts. Occasionally you'll see one leave and walk to the end of the lot. Then a co-worker will spawn right there and walk to the police station. It's a constant coming and going. Officer also get shuffled around when the lot is loaded (after returning from patrol, crimescene and arrest). This is the reason why you'll hardly ever meet your own sims if you only have two or three in the detective career yourself. The game "needs" seven or so officers to run the police station, but with the shift turnovers those seven in practice become a number closer to twenty.
At any time I always keep ca. 20 handmade police sims (played and unplayed, and at different career levels) in my rotational save and still get randoms now and then (that get deleted on the spot).
