When processing a vehicle linked to a homicide, what should be done first?

When processing a vehicle linked to a homicide, the initial step should focus on collecting trace evidence from the interior. This is vital because trace evidence—such as hair, fibers, glass, and other minute particles—can provide significant insights into the crime and its circumstances. By collecting this evidence first, investigators can preserve its integrity and avoid contamination that could occur from subsequent actions, such as moving or disturbing the vehicle.

In addition, trace evidence collected from the interior can potentially link a suspect to the crime scene or victim, revealing crucial details regarding the interaction that took place within the vehicle. This initial step underscores the importance of evidence preservation and the systematic approach necessary for thorough crime scene analysis. Other steps, like processing for fingerprints or checking the trunk, may come later in the investigation once the primary evidence from the interior has been obtained and documented.