Crime Scene Procedures: The 7 S's

When investigators arrive at a crime scene, they follow seven critical steps known as the 7 S's. These steps ensure nothing is overlooked and evidence remains uncontaminated.

The process begins with securing the crime scene, where initial police officers rope off the area and prioritize safety. They limit who can enter, create a detailed logbook of everyone present, and call for specialized help when needed. This critical first step prevents evidence contamination.

Next comes separating the witnesses, which prevents people from influencing each other's accounts. Investigators ask key questions: When and where did the crime occur? Where were you when it happened? Who was the victim or suspect? Who reported the crime? This information provides multiple perspectives on what happened.

Real-World Tip: Think about why police immediately put up yellow tape at crime scenes. It's not just for show—it's the first crucial step in preserving evidence that might solve the case!

Processing the Scene: From Scanning to Collection

After securing the scene and separating witnesses, investigators scan the scene to get an overview and identify both primary and secondary crime scenes. This helps them determine where to focus their photography efforts.

Seeing the scene comes next through detailed photography. Investigators take wide-angle shots from multiple perspectives and close-ups of key evidence. Some photos include measurement tools (scalers) to document size accurately.

Investigators then create detailed sketches with important elements: scale, north direction, case number, date, location, and the sketcher's name. For finding evidence, they use systematic search patterns like grid, linear, quadrant/zone, or spiral methods to ensure nothing is missed.

Finally, securing and collecting evidence requires precise handling. Evidence goes into paper (never plastic) containers using tools like flashlights and forceps to avoid contamination. Each item receives detailed labeling with the case number, description, recovery information, and names of those involved. The chain of custody documentation tracks everyone who handles the evidence afterward—a crucial step for court proceedings.

Test Prep Alert: The specific labeling requirements for evidence are frequently tested! Make sure you can list all the required elements: case number, item number, description, victim name, collection date/time, collector's name, and suspect's name (if known).