The Crime Scene
Police are usually the first to arrive at the scene - if the perpetrator is still there they arrest him, and if an ambulance is needed they call one.They may collect evidence.
Crime scene investigators will arrive to collect evidence, the District Attorney may go to the scene, and a medical examiner/coroner will be there if necessary. Detective will also be called to the scene. Any specialists needed will be called.
Crime Scene Guidelines - Procedure Search Operations of a Crime Scene
1. Preparation to move into scene, which officer is going where.
2. Initiate Preliminary Survey of scene
3. Conduct Detailed Search and Collect Physical Evidence
4. Prepare Narrative Description, use evidence to come up with a potential timeline of what happened
5. Make a rough sketch of the scene.
6. Interview witnesses, obtain as much information as the warrant allows. Create possible scenarios to what happened, if possible review footage taken by security cameras or review any other recording devices
7. Conduct final survey.
8. Release crime scene.