I am a third-grade detective, which is lowest. Good detective work and popularity with one's bosses will get one promoted. Good political connections don't hurt, either. In a way, this is a little similar to your hard-core code writers who never want to be managers. There are first-grade detectives in my office who work only homicides, who earn more than the lieutenant who commands our squad, and who wouldn't want to be anywhere else in the hierarchy.
Pay is a constant subject of conversation.
There seems to be a general consensus that there ought to be more of it, but there is endless debate over the best pension strategy, what one should do in one's last years to maximize one's pension and whether one is going to leave after 20 years. Some pension money is available before 20, but unless one is leaving for a spectacularly profitable second career, it is wise to stay at least 20 years. The pension is the truly great benefit to the job. It is virtually guaranteed and it allows a cop to choose either a second career where making money isn't that important as it was or one where the added pension money can make life much sweeter. I haven't figured out what I will do in 10 years.