Due to the diverse nature of criminal activity, specialised squads and offices have been developed to investigate crimes, which fall within a particular area of expertise. They all have their own agenda and parameters within which they work.

The role of detectives within the State Crime Squads and Regions is to contribute to the detection and apprehension of offenders and the reduction of crime by conducting thorough investigations into criminal offences. The major challenge of the position is to attain proficiency in criminal investigation techniques.

Officers are required to deal with complaints and queries from the general public and to ascertain the value of evidence gathered, with a view to preferring charges, ensure that investigations are brought to a satisfactory conclusion by completing inquiries into criminal offences, locate and secure any physical and forensic evidence from crime scenes and other sources during investigations, Ensure that all physical and forensic evidence is examined and reported on by the appropriate scientific or technical authority and conduct thorough interviews of witnesses and suspects during investigations, in accordance with recognised techniques and guidelines.

Officers in this line of work are referred to as Detective and work in formal civilian attire.

Selection as a Detective is competitive and only open to current serving officers. Due to a requirement of already displaying thorough investigation and interviewing techniques, applicants are required to have had a number of year's experience in operational policing beforehand.