• In the absence of a ruler, place another object next to the detail for scaling purposes. This object is to be safely stored and provided along with the photograph when handing the information to criminal investigators. • Ensure that the detail is proper illuminated, avoiding overexposure or under-exposure to light as much as possible.98 Use a flashlight or other external light source if necessary. 3.2 Documenting and Recording a Crime Scene This section outlines how to secure a crime scene and record observations of it. The objective of documenting and recording a crime scene is to correctly interpret the facts, and to reconstruct and uncover the events leading up to and including the alleged abuse or crime. 99 Crime scene investigation is a process that aims to record the scene as it is first encountered and recognize and collect all physical information potentially relevant to investigating the crime. 100 3.2.1 In Principle, Refrain From Any Investigations As was stipulated earlier in this Handbook, in principle, investigations should only be conducted by those that are professionally trained in this. Civil society actors may, however, help preserve the crime scene and make professional investigators aware of the situation, and in other ways contribute to ensuring that professional investigators can conduct their investigations as effectively as possible. Only when professional and reliable investigators cannot access the crime scene in time before the information would lose its value may unofficial investigators consider taking action. However, they should do so only in accordance with the guidelines that are provided in this Handbook. For example, as discussed in Chapter 2, they should always uphold the 98 Brian Gestring, A FORENSIC SCIENTIST’S GUIDE TO PHOTOGRAPHY 23-5 (2007), available at http://www.forensictv.net/Downloads/digital_imaging_and_photography/forensic_scientists_guide_to_phot ography_by_brian_gestring.pdf. 99 United Nations Office on Drugs and Crime, CRIME SCENE AND PHYSICAL EVIDENCE AWARENESS FOR NON-FORENSIC PERSONNEL, 1 (2009), available at http://www.unodc.org/documents/scientific/Crime_scene_awareness__Ebook.pdf. 100 United Nations Office on Drugs and Crime, CRIME SCENE AND PHYSICAL EVIDENCE AWARENESS FOR NON-FORENSIC PERSONNEL, 4 (2009). 77