Some questions about police investigation/policies/information spreading:
1. Would it be conceivable for say a robbery detective to know who's been assigned to a high-profile murder? Would this be consider classified/inner-department knowledge or could she mention this to a civilian without breaking policy? This would a serial murder case covered in the papers.
2. In a medium-large (dangerous) city, if several homicide detectives were involved in a serial murder case, would they possibly pull others from other departments to help cover other cases/handle grunt work?
3. In cases where there's clearly some brand of crazy happening, do police consult psychologists? Has does that work?