At the crime scene Crime scene investigators only have one chance to get things right!! Successfully prosecuting suspects depend on how evidence is handled. Cases where improper handling of crime scene evidence may have impacted the outcome of a case: • JonBenet Ramsey • O.J. Simpson
At the Crime Scene Protect: When a crime is called in, the first officer at the scene should: • protect the scene to prevent the destruction of evidence • anyone not involved in the investigation should be kept out • no one should use the toilet, towels, phone, lights, etc.
At the Crime Scene Record: When an investigator (detective) first arrives at the scene they do the following: • interview witnesses • consider legal aspects (search warrants) • take meticulous notes (these may be needed later in court) • document the scene by making a rough sketch • take photographs • Investigators motto: “Eyes open, mouth closed, hands in pockets”
At the Crime Scene Photographs ▪ Do not take the place of the sketch ▪ Should include location, overall photos of the scene, evidence and close-up(items + items with a ruler) ▪ Videotaping is becoming more popular
At the Crime Scene Notes: • There cannot be enough notes taken • Notes should be in chronological order, detailed, and thorough • Notes are never to be discarded as they could be the only source • of information to refresh memory
At the Crime Scene Sketch: • A smooth sketch is done at the lab. • A rough sketch is done at the crime scene. • It includes measurements, • Compass direction, and a legend. • ● Measurements are always taken from 2 fixed points. • It includes a scale, • Compass direction, and a legend. • This is what is shown to a jury but the rough sketch is never discarded
At the Crime Scene Search: • Depending on the location of the crime scene one of four search • patterns will be used to look for evidence Quadrant Lane Grid Spiral
At the Crime Scene Collect: Evidence that is easily lost or fragile is collected first. We will talk later about how evidence is collected such as: Blood Ballistics Trace Evidence
At the Crime Scene Collect: ▪ Evidence should not be removed from its source when possible. ▪ Evidence should be packaged to prevent breakage, spoilage and contamination( individually) ▪ Evidence should be marked with the recovering officer’s initials, the location and the date. ***A chain of custody must be maintained!! It’s a list of all persons who came into possession of an item of evidence.
At the Crime Scene People found at the crime scene: • Police Officer: Protect the scene. • Medical Examiner: Declare death, I.D. the body, determine • cause, manner, and time of death. • CSI Unit: Collect evidence, photo crime scene, produce rough • and smooth sketches. • Detective: Interview witnesses, suspects, puts all the pieces • of the puzzle together.