how to hire a criminalist's main job? (Police Tactics: Imperio)

Any rookie can do patrol, criminalist, detective, and so on. - have the relevant skills from the balls, which earns the unit. As soon as the unit attains 4 points of ability - he will automatically gain a specialization and are placed in the right room. Therefore, the rookie acquired points for various useful actions it is necessary to add in criminology. And after level 4 criminology - he will automatically become a CSI.