Could be - perpetrator, victim, witness or accomplice.
Yes, it is true that the defendant was present at the scene of the crime, Your Honor.
They are known as crime scene investigator/examiner, crime scene photographer, crime photographer.
To the best of my knowledge the professional person who investigates a crime where it was perpetrated is called "a crime on scene investigator".
A piece of fingernail found at the crime scene
A bystander is a person who is present at an incident or event, but does not participate. An example is someone that may have seen a crime scene or a spectator at an event.
Yes, there is the primary crime scene and the secondary crime scene. For example, if a body was found in a trash can but there is no evidence that the person was killed there then it means the person was killed somewhere else. The primary crime scene is where the person was killed and the secondary crime scene is where the body was dumped.
Hair found at a crime scene contains DNA, which can be compared to a suspect's or victim's DNA to establish a link. Hair also has unique characteristics like color, length, and treatment, which can be used as evidence in investigations. Analyzing hair evidence can help to identify individuals present at the crime scene.
recover it from a person or crime scene
They are called the Coroner.
The henchmen were subdued with the help of the police present at the crime scene.
the FAO (first attending officer) is first on the scene when called to a crime.
First Responder