For a criminal investigation, police officers need to keep several key elements in mind. There are some on-scene and some immediately-after steps to consider and some ways to record evidence so that detectives can properly conduct the bulk of the investigation as time passes. Once the crime scene gets ‘cold’, i.e., 24 hours pass, chances of catching the culprit gets lowered significantly.
1. If police officers arrive and the crime is in progress, the culprit must be stopped and apprehended immediately.
2. If the crime has already happened, officers must locate suspects and canvas the area to look for witnesses and question them.
3. The area must be cordoned off to wait for CSIs and/or MEs.
4. CSIs should preserve crime scenes and conduct a systematic search for evidence
5. Any and all evidence or potential evidence must be collected.
6. Bodies of deceased victims should be traced, photographed by forensic photographers, and examined by MEs before being transported to the morgue.
7. All analysis and witness reports are collected and lab reports come in to assist the detectives.
8. Evidence is further analyzed, suspects are identified and interrogated, and conclusions are made to apprehend the culprit.
For a private sector investigation to evolve into a public sector investigation, one major prerequisite that needs to be fulfilled is that the issue being investigated must be a criminal offense. Public sector resources are already limited and therefore may be wasted on private matters. For an investigation to evolve into a public sector investigation, the primary private investigator must prove to the regulating body, such as the sheriff’s department or the local police station, that the issue has transitioned from a private matter to a public offense. Public sector investigations are exclusive to crimes while private sector investigators may look into any civil or private matter, no matter how small.
Having said that, governments often also step in for high-profile individuals, assisting them with private issues, or may step in from time to time in private investigations to promote goodwill. This is because private investigations can get very expensive over time because of the equipment required. Public sector investigators often have access to such equipment from the government and therefore don’t have to pay from their pockets, unlike those in the private sector.
It isn’t uncommon to see the public sector (the government) to be working with private investigators (PIs). This mostly happens if a private investigator has undertaken a government contract for investigative service. While in some cases, the government pays detectives for their services rendered as a form of contractual payment. In other cases, the government offers a ‘bounty’, i.e., the private investigator only gets paid if the culprit is apprehended as a result of this partnership. This is very common in the world of cybercrime.
Another instance where the public and private sector may work together is that if, after investigations, it gets proven by the private investigator that there has been a crime, the public sector may get involved while letting the private investigator lead their own investigation. The police may assist the private investigator on a small level. However, this collaboration often gets turned around, i.e., the PI becomes the ‘assistor’ if public sector investigators get involved as well.