If we don't have any criminal jobs, then everyone will just be a CEO for their high paycheck. And in most CRPGs, cops DO spawn with weapons, and it's pretty easy to arrest a criminal, you just need good co-ordination with the other police units.
Unless this server enforces roleplaying, then there's no reason to remove the criminal job tree. Crime sprees are the basis of the economy in the majority of servers, and removing that will lead to everyone waiting for ages just to gain their education from pay-checks instead of looting corpses and arresting criminals. The cops vs robbers aspect is what most people join for, anyway. If done right, then things can get really interesting for the server and the city if you look at it from an RP perspective even though no one really role-plays.
Does anyone remember bbs' city rpg? It got a little crazy with the glitches and overwhelmingly valuable drugs and the ability to abuse the economy. But with that money, came multiple player-made factions, the two largest being "Altosk" (My gang of friends and lackeys) and G.U.A.R.D. (Guardians United Against Radical Destruction, a bunch of "mercenaries" that arrested any and every criminal) Those two factions attacked each-other constantly, both of which had traitors, spies, and cops within them.
(Will add more to this post)