Why do detectives in the US have to start their careers as beat cops?

Question

I understand why it might have started out this way when police forces were first becoming established, but why does it continue to be this way?

These seem like entirely different skill sets, and surely it’s easier to teach them basic police skills as part of their training rather than having them stay as beat cops for several years first.

In: Other

Answer 1

Ranking? You rank up just like many professions.